refactor(ai): trim effort update comments and tests

Co-authored-by: nexxeln <95541290+nexxeln@users.noreply.github.com>

packages/ai/AGENTS.md

@@ -165,6 +165,10 @@ Native chronological system messages are route/model-specific. Open Responses lo
 
 The wrapped-user fallback preserves ordering while visibly lowering authority. Never silently pass a raw chronological `role: "system"` through a route that might reject it. Do not insert raw retrieved documents, tool output, or web content into privileged chronological system updates; keep untrusted content in ordinary user/tool channels.
 
+### Effort Updates
+
+`Message.effort({ effort, previous })` is a chronological "reasoning effort changed here" marker (`undefined` means the model default). Changing a top-level effort invalidates the whole provider prompt cache, so protocols with a native per-message update (`Protocol.supportsEffortUpdates`) keep the top-level effort at the first marker's `previous` and lower each marker in place: Anthropic Messages emits an empty `role: "system"` message with `output_config.effort` plus the `mid-conversation-output-config-2026-07-01` beta, and OpenAI Responses emits `configuration_update` items. `applyEffortUpdates` runs in `prepareRequest` and strips the markers for every other route, so a protocol without support keeps today's plain top-level behaviour. When the last marker disagrees with the effort the request asks for (reverted or forked history), `resolveEffortUpdates` strips the markers and falls back to a plain top-level change.
+
 ### Tools
 
 Tool loops are represented in common messages and events:

packages/ai/src/cache-policy.ts

@@ -12,6 +12,7 @@
 // count against the four-breakpoint budget; auto only fills remaining slots.
 import { CacheHint, type CachePolicy, type CachePolicyObject } from "./schema/options.js"
 import { LLMRequest, Message, ToolDefinition, type ContentPart, type ToolEntry } from "./schema/messages.js"
+import { effortUpdate } from "./effort-updates.js"
 
 const AUTO: CachePolicyObject = {
   tools: true,
@@ -121,9 +122,15 @@ const markMessages = (
     return markMessageAt(messages, lastIndexOfRole(messages, "user"), hint, budget)
   if (strategy === "latest-assistant")
     return markMessageAt(messages, lastIndexOfRole(messages, "assistant"), hint, budget)
-  const start = Math.max(0, messages.length - strategy.tail)
+  let start = messages.length
+  let remaining = strategy.tail
+  while (remaining > 0 && start > 0) {
+    start -= 1
+    if (effortUpdate(messages[start]!) === undefined) remaining -= 1
+  }
   let next = messages
-  for (let i = start; i < messages.length; i++) next = markMessageAt(next, i, hint, budget)
+  for (let i = start; i < messages.length; i++)
+    if (effortUpdate(messages[i]!) === undefined) next = markMessageAt(next, i, hint, budget)
   return next
 }
 

packages/ai/src/effort-updates.ts

@@ -0,0 +1,27 @@
+// A top-level reasoning effort change invalidates the whole provider prompt cache, so a
+// mid-conversation switch travels as a `Message.effort(...)` marker: protocols with a native
+// per-message update freeze the top-level effort and lower the markers; every other route strips them.
+import { LLMRequest, type EffortPart, type Message } from "./schema/messages.js"
+
+export const effortUpdate = (message: Message): EffortPart | undefined => {
+  if (message.role !== "system" || message.content.length !== 1) return undefined
+  const part = message.content[0]
+  return part.type === "effort" ? part : undefined
+}
+
+export const stripEffortUpdates = (request: LLMRequest) => {
+  const messages = request.messages.filter((message) => effortUpdate(message) === undefined)
+  return messages.length === request.messages.length ? request : LLMRequest.update(request, { messages })
+}
+
+export const applyEffortUpdates = (request: LLMRequest): LLMRequest =>
+  request.model.route.supportsEffortUpdates?.(request) ? request : stripEffortUpdates(request)
+
+// The markers must end at `current`: `revert.ts` never touches `session.model` and forks may select
+// another variant, so on disagreement fall back to a plain top-level change instead of misreporting effort.
+export const resolveEffortUpdates = (request: LLMRequest, current: string | undefined) => {
+  const updates = request.messages.flatMap((message) => effortUpdate(message) ?? [])
+  if (updates.length === 0) return { request, effort: current }
+  if (updates.at(-1)?.effort !== current) return { request: stripEffortUpdates(request), effort: current }
+  return { request, effort: updates[0]?.previous }
+}

packages/ai/src/protocols/anthropic-messages.ts

@@ -27,6 +27,7 @@ import {
 } from "../schema/index.js"
 import { JsonObject, optionalArray, optionalNull, ProviderShared } from "./shared.js"
 import { classifyProviderFailure } from "../provider-error.js"
+import { effortUpdate, resolveEffortUpdates } from "../effort-updates.js"
 import * as Cache from "./utils/cache.js"
 import { Lifecycle } from "./utils/lifecycle.js"
 import { ToolSchemaProjection } from "./utils/tool-schema.js"
@@ -36,6 +37,7 @@ const ADAPTER = "anthropic-messages"
 export const DEFAULT_BASE_URL = "https://api.anthropic.com/v1"
 export const PATH = "/messages"
 export const DEFAULT_MAX_TOKENS = 32_000
+const DEFAULT_EFFORT = "high"
 
 const SSE_EVENTS = new Set([
   "message",
@@ -286,7 +288,11 @@ type AnthropicToolResultBlock = Schema.Schema.Type<typeof AnthropicToolResultBlo
 const AnthropicMessage = Schema.Union([
   Schema.Struct({ role: Schema.Literal("user"), content: Schema.Array(AnthropicUserBlock) }),
   Schema.Struct({ role: Schema.Literal("assistant"), content: Schema.Array(AnthropicAssistantBlock) }),
-  Schema.Struct({ role: Schema.Literal("system"), content: Schema.Array(AnthropicTextBlock) }),
+  Schema.Struct({
+    role: Schema.Literal("system"),
+    content: Schema.Array(AnthropicTextBlock),
+    output_config: Schema.optional(Schema.Struct({ effort: Schema.String })),
+  }),
 ]).pipe(Schema.toTaggedUnion("role"))
 type AnthropicMessage = Schema.Schema.Type<typeof AnthropicMessage>
 
@@ -877,6 +883,12 @@ const lowerMessages = Effect.fn("AnthropicMessages.lowerMessages")(function* (
 
   for (const [index, message] of request.messages.entries()) {
     if (message.role === "system") {
+      const update = effortUpdate(message)
+      if (update) {
+        // Accepted at any position, so the text-update placement rules do not apply.
+        messages.push({ role: "system", content: [], output_config: { effort: update.effort ?? DEFAULT_EFFORT } })
+        continue
+      }
       if (splitsLocalToolResults(request.messages, index))
         return yield* invalid("Anthropic Messages system updates cannot split a local tool call from its tool result")
       if (supportsNativeSystemUpdates(request) && canUseNativeSystemUpdate(request, index)) {
@@ -1034,18 +1046,11 @@ const resolveOptions = Effect.fn("AnthropicMessages.resolveOptions")(function* (
     ProviderShared.isRecord(rawOutputConfig) && ProviderShared.isRecord(rawOutputConfig.format)
       ? (rawOutputConfig.format as { type: "json_schema"; schema: Record<string, unknown> })
       : undefined
-  const output_config =
-    outputConfigEffort === undefined && outputConfigFormat === undefined
-      ? undefined
-      : {
-          ...(outputConfigEffort === undefined ? {} : { effort: outputConfigEffort }),
-          ...(outputConfigFormat === undefined ? {} : { format: outputConfigFormat }),
-        }
   const thinking = yield* resolveThinking(input?.thinking)
   return {
     thinking: applyThinkingBindingDefault(request.model, thinking),
     effort: outputConfigEffort,
-    output_config,
+    format: outputConfigFormat,
     service_tier,
     metadata,
     container,
@@ -1054,15 +1059,30 @@ const resolveOptions = Effect.fn("AnthropicMessages.resolveOptions")(function* (
   }
 })
 
+// Accept gateway namespaces and Vertex suffixes without treating a snapshot date as a minor version.
+const claudeVersion = (id: string) => {
+  const match = /(?:^|[./])claude-(?<family>[a-z]+)-(?<major>\d+)(?:[.-](?<minor>\d{1,2}))?(?:$|[-:@])/.exec(
+    id.toLowerCase(),
+  )?.groups
+  if (!match) return undefined
+  return { family: match.family, major: Number(match.major), minor: Number(match.minor ?? 0) }
+}
+
 const supportsThinkingBlockBinding = (model: LLMRequest["model"]) => {
   const override = model.compatibility?.supportsThinkingBlockBinding
   if (override !== undefined) return override
-  // Accept gateway namespaces and Vertex suffixes without treating a snapshot date as a minor version.
-  const version = /(?:^|[./])claude-[a-z]+-(?<major>\d+)(?:[.-](?<minor>\d{1,2}))?(?:$|[-:@])/i.exec(model.id)?.groups
-  if (!version) return false
-  const major = Number(version.major)
-  const minor = Number(version.minor ?? 0)
-  return major > 5 || (major === 5 && minor >= 1)
+  const version = claudeVersion(model.id)
+  return version !== undefined && (version.major > 5 || (version.major === 5 && version.minor >= 1))
+}
+
+const supportsEffortUpdates = (model: LLMRequest["model"]) => {
+  const override = model.compatibility?.supportsEffortUpdates
+  if (override !== undefined) return override
+  const version = claudeVersion(model.id)
+  if (version === undefined) return false
+  if (version.family === "opus") return version.major >= 5
+  if (version.family !== "fable" && version.family !== "mythos") return false
+  return version.major > 5 || (version.major === 5 && version.minor >= 1)
 }
 
 const applyThinkingBindingDefault = (model: LLMRequest["model"], thinking: AnthropicThinking | undefined) => {
@@ -1104,13 +1124,15 @@ const fromRequest = Effect.fn("AnthropicMessages.fromRequest")(function* (reques
   const management = yield* ProviderShared.validateWith(
     Schema.decodeUnknownEffect(Schema.UndefinedOr(ContextManagement)),
   )(request.providerOptions?.contextManagement)
+  const options = yield* resolveOptions(request)
+  const updates = resolveEffortUpdates(request, options.effort)
   const generation = request.generation
   const toolSchemaCompatibility = request.model.compatibility?.toolSchema
   // Allocate the 4-breakpoint budget in invalidation order: tools → system →
   // messages. Tools live highest in the cache hierarchy, so when callers
   // over-mark we keep their tool hints and shed the message-tail ones first.
   const breakpoints = Cache.newBreakpoints(ANTHROPIC_BREAKPOINT_CAP)
-  const flattened = ProviderShared.flattenToolRequest(request)
+  const flattened = ProviderShared.flattenToolRequest(updates.request)
   const tools =
     flattened.tools.length === 0
       ? undefined
@@ -1138,7 +1160,13 @@ const fromRequest = Effect.fn("AnthropicMessages.fromRequest")(function* (reques
       `Anthropic Messages: dropped ${breakpoints.dropped} cache breakpoint(s); the API allows at most ${ANTHROPIC_BREAKPOINT_CAP} per request.`,
     )
   }
-  const options = yield* resolveOptions(request)
+  const output_config =
+    updates.effort === undefined && options.format === undefined
+      ? undefined
+      : {
+          ...(updates.effort === undefined ? {} : { effort: updates.effort }),
+          ...(options.format === undefined ? {} : { format: options.format }),
+        }
   const body = {
     model: request.model.id,
     system,
@@ -1152,7 +1180,7 @@ const fromRequest = Effect.fn("AnthropicMessages.fromRequest")(function* (reques
     top_k: generation?.topK,
     stop_sequences: generation?.stop,
     thinking: options.thinking,
-    output_config: options.output_config,
+    output_config,
     // top-level passthrough per SDK MessageCreateParamsBase:4638,4643,4649,4654,4670
     cache_control: options.cache_control,
     container: options.container,
@@ -1677,6 +1705,7 @@ export const protocol = Protocol.make({
     }),
     step,
   },
+  supportsEffortUpdates: (request) => supportsEffortUpdates(request.model),
 })
 
 export const transport = <
@@ -1715,6 +1744,9 @@ function requiredBetaHeaders(body: Pick<AnthropicMessagesBody, "messages" | "con
   )
   if (requestsCompaction || replaysCompaction) betas.push("compact-2026-01-12")
 
+  if (body.messages.some((message) => message.role === "system" && message.output_config !== undefined))
+    betas.push("mid-conversation-output-config-2026-07-01")
+
   const thinking = body.thinking
   if (thinking && thinking.type !== "disabled" && thinking.block_binding)
     betas.push("thinking-binding-controls-2026-08-01")

packages/ai/src/protocols/open-responses-channel.ts

@@ -18,7 +18,6 @@ const WebSocketResponseCreate = Schema.StructWithRest(Schema.Struct({ type: Sche
 ])
 const decodeMessage = ProviderShared.validateWith(Schema.decodeUnknownEffect(WebSocketResponseCreate))
 const encodeMessage = Schema.encodeSync(Schema.fromJsonString(WebSocketResponseCreate))
-const decodeEvent = Schema.decodeUnknownEffect(OpenResponses.protocol.stream.event)
 
 export interface Options {
   readonly id: string
@@ -27,6 +26,7 @@ export interface Options {
   readonly enabled?: (url: string) => boolean
   readonly url?: (url: string) => string
   readonly headers?: (headers: Headers.Headers) => Headers.Headers
+  readonly continuation?: OpenResponsesContinuation.Shape
 }
 
 export interface Prepared {
@@ -60,7 +60,7 @@ const driver = (options: Options, body: string): WebSocketChannelDriver => {
       }),
     observe: (_create, frame) =>
       Effect.gen(function* () {
-        const event = yield* decodeEvent(frame).pipe(
+        const event = yield* OpenResponses.decodeChannelEvent(frame).pipe(
           Effect.mapError((cause) =>
             ProviderShared.eventError(options.id, `Invalid ${options.name} WebSocket event`, frame, cause),
           ),
@@ -163,6 +163,7 @@ export const transport = <Body>(options: Options): Transport<Body, Prepared, str
                     request: create.request,
                     message: create.message,
                     base,
+                    continuation: options.continuation,
                   }),
                 }
               })

packages/ai/src/protocols/open-responses-continuation.ts

@@ -6,7 +6,6 @@ import { OpenResponses } from "./open-responses.js"
 
 const PROTOCOL = "open-responses.websocket.v1"
 const VERSION = 1
-const decodeEvent = Schema.decodeUnknownEffect(OpenResponses.protocol.stream.event)
 
 interface CheckpointValue {
   readonly version: typeof VERSION
@@ -15,12 +14,19 @@ interface CheckpointValue {
   readonly output: ReadonlyArray<unknown>
 }
 
+/**
+ * Fields to send next to `previous_response_id` on an incremental step, or undefined to send the step in full.
+ * Whether omitted fields carry over from the continued response is provider behavior the route must know.
+ */
+export type Shape = (request: Readonly<Record<string, unknown>>) => Readonly<Record<string, unknown>> | undefined
+
 export interface DriverInput {
   readonly id: string
   readonly name: string
   readonly request: Readonly<Record<string, unknown>>
   readonly message: string
   readonly base: WebSocketChannelDriver
+  readonly continuation?: Shape
 }
 
 const checkpointValue = (checkpoint: ChannelCheckpoint | undefined): CheckpointValue | undefined => {
@@ -127,22 +133,26 @@ const rejected = (
 
 export const driver = (input: DriverInput): WebSocketChannelDriver => {
   const { previous_response_id: _previousResponseID, ...request } = input.request
+  const shape = input.continuation ?? ((fields: Readonly<Record<string, unknown>>) => fields)
   let output: OpenResponses.StreamItem[] = []
   return {
     create: (checkpoint) =>
       Effect.sync(() => {
         output = []
         const previous = checkpointValue(checkpoint)
-        const delta = previous ? incremental(request, previous) : undefined
-        if (!previous || !delta) return { message: ProviderShared.encodeJson(request), mode: "full" as const }
+        // Ask the route first: diffing the whole history is wasted when it declines the continuation.
+        const fields = previous ? shape(request) : undefined
+        const delta = previous && fields ? incremental(request, previous) : undefined
+        if (!previous || !fields || !delta)
+          return { message: ProviderShared.encodeJson(request), mode: "full" as const }
         return {
-          message: ProviderShared.encodeJson({ ...request, input: delta, previous_response_id: previous.responseID }),
+          message: ProviderShared.encodeJson({ ...fields, input: delta, previous_response_id: previous.responseID }),
           mode: "incremental" as const,
         }
       }),
     observe: (create, frame) =>
       Effect.gen(function* () {
-        const event = yield* decodeEvent(frame).pipe(
+        const event = yield* OpenResponses.decodeChannelEvent(frame).pipe(
           Effect.mapError((cause) =>
             ProviderShared.eventError(input.id, `Invalid ${input.name} WebSocket event`, frame, cause),
           ),
@@ -195,4 +205,4 @@ export const driver = (input: DriverInput): WebSocketChannelDriver => {
   }
 }
 
-export const OpenResponsesContinuation = { driver } as const
+export * as OpenResponsesContinuation from "./open-responses-continuation.js"

packages/ai/src/protocols/open-responses.ts

@@ -1,4 +1,4 @@
-import { Effect, Option, Schema } from "effect"
+import { Effect, Option, Schema, SchemaGetter } from "effect"
 import type { Content } from "@opencode/schema/tool"
 import { HttpTransport } from "../route/transport/index.js"
 import { Protocol } from "../route/protocol.js"
@@ -20,6 +20,7 @@ import {
 } from "../schema/index.js"
 import { JsonObject, optionalArray, optionalNull, ProviderShared } from "./shared.js"
 import { classifyProviderFailure } from "../provider-error.js"
+import { effortUpdate } from "../effort-updates.js"
 import { OpenResponsesOptions } from "./utils/open-responses-options.js"
 import { Lifecycle } from "./utils/lifecycle.js"
 import { ToolSchemaProjection } from "./utils/tool-schema.js"
@@ -164,6 +165,13 @@ export const CompactionItem = Schema.Struct({
   encrypted_content: Schema.String,
 })
 
+// Kept out of the baseline `InputItem` union: only the OpenAI extension accepts it.
+export const ConfigurationUpdate = Schema.Struct({
+  type: Schema.Literal("configuration_update"),
+  reasoning: Schema.Struct({ effort: OpenResponsesOptions.ReasoningEffort }),
+})
+type ConfigurationUpdate = Schema.Schema.Type<typeof ConfigurationUpdate>
+
 export const InputItem = Schema.Union([
   CompactionItem,
   Schema.Struct({ role: Schema.tag("system"), content: Schema.String }),
@@ -208,6 +216,7 @@ export type HostedToolReplayItem = {
 type LoweredInputItem =
   | OpenResponsesInputItem
   | HostedToolReplayItem
+  | ConfigurationUpdate
   | {
       readonly type: "message"
       readonly id?: string
@@ -325,9 +334,8 @@ export const StreamItem = Schema.StructWithRest(
 export type StreamItem = Schema.Schema.Type<typeof StreamItem>
 export type OutputItem = StreamItem & { readonly id: string }
 
-// The Responses schema puts streaming error details at the top level and
-// response failures under `response.error`. WebSocket failures use an
-// event-level `error` envelope, so accept all three shapes here.
+// Responses-compatible providers put streaming error details at the top level or
+// under `error`, and response failures under `response.error`. Accept all three shapes.
 // https://www.openresponses.org/specification
 const OpenResponsesErrorPayload = Schema.Struct({
   type: optionalNull(Schema.String),
@@ -401,10 +409,39 @@ export const Event = Schema.StructWithRest(
     headers: Schema.optional(Schema.Unknown),
   }),
   [Schema.Record(Schema.String, Schema.Unknown)],
+).pipe(
+  Schema.decode({
+    decode: SchemaGetter.transform((event) => {
+      if (event.type !== "error" || event.error != null) return event
+      const { code, message, param, ...rest } = event
+      if (code === undefined && message === undefined && param === undefined) return event
+      // Flat errors (for example, Meta's) can also arrive through generic Responses endpoints.
+      return { ...rest, error: { code, message, param } }
+    }),
+    encode: SchemaGetter.passthrough(),
+  }),
 )
 export type Event = Schema.Schema.Type<typeof Event>
 export type NormalizedEvent = Event & { readonly item?: OutputItem | null }
 
+const decodeEventValue = Schema.decodeUnknownEffect(Event)
+const decodeFrame = Schema.decodeUnknownEffect(ProviderShared.Json)
+
+/**
+ * Decodes one WebSocket frame. xAI answers a rejected `response.create` with `{ "error": { "message", "type" } }` and no
+ * event type; that envelope reads as an error event so the failure classifies instead of failing decoding.
+ */
+export const decodeChannelEvent = (frame: string) =>
+  decodeFrame(frame).pipe(
+    Effect.flatMap((value) =>
+      decodeEventValue(
+        ProviderShared.isRecord(value) && value.type === undefined && ProviderShared.isRecord(value.error)
+          ? { ...value, type: "error" }
+          : value,
+      ),
+    ),
+  )
+
 export interface ProviderAdapter {
   readonly id: string
   readonly name: string
@@ -606,6 +643,8 @@ const lowerToolResultOutput = Effect.fnUntraced(function* (
   return yield* Effect.forEach(content, (item) => lowerToolResultContentItem(item, request, adapter))
 })
 
+const DEFAULT_EFFORT = "medium"
+
 const lowerMessages = Effect.fn("OpenResponses.lowerMessages")(function* (
   request: LLMRequest,
   adapter: ProviderAdapter,
@@ -618,6 +657,14 @@ const lowerMessages = Effect.fn("OpenResponses.lowerMessages")(function* (
       Schema.decodeUnknownEffect(Schema.UndefinedOr(MessageMetadata)),
     )(message.providerMetadata?.[providerMetadataKey])
     if (message.role === "system") {
+      const update = effortUpdate(message)
+      if (update) {
+        // Consecutive updates are rejected, so a newer one replaces its predecessor.
+        const last = input.at(-1)
+        if (last !== undefined && "type" in last && last.type === "configuration_update") input.pop()
+        input.push({ type: "configuration_update", reasoning: { effort: update.effort ?? DEFAULT_EFFORT } })
+        continue
+      }
       input.push({
         role: "developer",
         content: ProviderShared.joinText(yield* ProviderShared.systemUpdateText(adapter.name, message)),
@@ -761,8 +808,7 @@ export const lowerConversation = Effect.fn("OpenResponses.lowerConversation")(fu
   }
 })
 
-export const lowerGeneration = (request: LLMRequest) => {
-  const options = OpenResponsesOptions.resolve(request)
+export const lowerGeneration = (request: LLMRequest, options = OpenResponsesOptions.resolve(request)) => {
   const generation = request.generation
   const cacheKey = ProviderShared.promptCacheKey(request)
   const parallelToolCalls = resolveParallelToolCalls(request)

packages/ai/src/protocols/openai-responses.ts

@@ -6,7 +6,9 @@ import { Endpoint } from "../route/endpoint.js"
 import { Protocol } from "../route/protocol.js"
 import { HttpTransport } from "../route/transport/index.js"
 import { LLMRequest, mergeJsonRecords, type JsonSchema, type ToolDefinition, type ToolEntry } from "../schema/index.js"
+import { resolveEffortUpdates } from "../effort-updates.js"
 import { OpenResponses } from "./open-responses.js"
+import { OpenResponsesOptions } from "./utils/open-responses-options.js"
 import { JsonObject, optionalArray, optionalNull, ProviderShared } from "./shared.js"
 import { OpenAIImage } from "./utils/openai-image.js"
 import { ResponsesHostedTools } from "./utils/responses-hosted-tools.js"
@@ -94,9 +96,15 @@ const OpenAIResponsesToolChoice = Schema.Union([
   Schema.Struct({ type: Schema.tag("image_generation") }),
 ])
 
+const OpenAIResponsesInputItem = Schema.Union([
+  OpenResponses.InputItem,
+  OpenAIResponsesHostedToolItem,
+  OpenResponses.ConfigurationUpdate,
+])
+
 const OpenAIResponsesCoreFields = {
   ...OpenResponses.coreFields,
-  input: Schema.Array(Schema.Union([OpenResponses.InputItem, OpenAIResponsesHostedToolItem])),
+  input: Schema.Array(OpenAIResponsesInputItem),
   tools: optionalArray(OpenAIResponsesTools),
   tool_choice: Schema.optional(OpenAIResponsesToolChoice),
   context_management: Schema.optional(
@@ -119,7 +127,7 @@ export type OpenAIResponsesBody = Schema.Schema.Type<typeof OpenAIResponsesBody>
 export const CompactionTrigger = Schema.Struct({ type: Schema.Literal("compaction_trigger") })
 const CheckpointBody = Schema.Struct({
   ...OpenAIResponsesBody.fields,
-  input: Schema.Array(Schema.Union([OpenResponses.InputItem, OpenAIResponsesHostedToolItem, CompactionTrigger])),
+  input: Schema.Array(Schema.Union([OpenAIResponsesInputItem, CompactionTrigger])),
   store: Schema.Literal(false),
   prompt_cache_retention: optionalNull(Schema.String),
   prompt_cache_options: optionalNull(
@@ -133,6 +141,14 @@ const adapter = {
   restoreHostedToolItem: (item: unknown) => (Schema.is(OpenAIResponsesHostedToolItem)(item) ? item : undefined),
 } satisfies OpenResponses.ProviderAdapter
 
+// Only GPT-6 Astra accepts `configuration_update`, and never alongside automatic `context_management` compaction.
+const supportsEffortUpdates = (request: LLMRequest) => {
+  if (request.providerOptions?.contextManagement !== undefined) return false
+  const override = request.model.compatibility?.supportsEffortUpdates
+  if (override !== undefined) return override
+  return /(?:^|\/)gpt-6-astra$/i.test(request.model.id)
+}
+
 const nativeImageToolInput = (tool: ToolDefinition) => {
   const native = tool.native?.openai
   return ProviderShared.isRecord(native) && native.type === "image_generation" ? native : undefined
@@ -189,10 +205,12 @@ const fromRequest = Effect.fn("OpenAIResponses.fromRequest")(function* (request:
   const management = yield* ProviderShared.validateWith(
     Schema.decodeUnknownEffect(Schema.UndefinedOr(ContextManagement)),
   )(request.providerOptions?.contextManagement)
+  const options = OpenResponsesOptions.resolve(request)
+  const updates = resolveEffortUpdates(request, options.reasoningEffort)
   const toolSchemaCompatibility = request.model.compatibility?.toolSchema
   return yield* decodeBody({
-    ...(yield* OpenResponses.lowerConversation(request, adapter)),
-    ...OpenResponses.lowerGeneration(request),
+    ...(yield* OpenResponses.lowerConversation(updates.request, adapter)),
+    ...OpenResponses.lowerGeneration(request, { ...options, reasoningEffort: updates.effort }),
     context_management: management?.map((edit) => ({ type: edit.type, compact_threshold: edit.compactThreshold })),
     tools:
       request.tools.length === 0
@@ -295,6 +313,7 @@ export const protocol = Protocol.make({
     step,
     terminal: OpenResponses.terminal,
   },
+  supportsEffortUpdates,
 })
 
 const endpoint = Endpoint.path<OpenAIResponsesBody>(PATH, { baseURL: DEFAULT_BASE_URL })

packages/ai/src/protocols/utils/open-responses-options.ts

@@ -1,12 +1,7 @@
 import { Option, Schema } from "effect"
-import type { LLMRequest } from "../../schema/index.js"
+import { ReasoningEffort, ReasoningEfforts, type LLMRequest } from "../../schema/index.js"
 
-export const ReasoningEfforts = ["none", "minimal", "low", "medium", "high", "xhigh", "max"] as const
-export type ReasoningEffort = (typeof ReasoningEfforts)[number] | (string & {})
-export const ReasoningEffort = Schema.declare<ReasoningEffort>(
-  (value): value is ReasoningEffort => typeof value === "string",
-  { title: "ReasoningEffort" },
-)
+export { ReasoningEffort, ReasoningEfforts }
 
 export const TextVerbosities = ["low", "medium", "high"] as const
 export type TextVerbosity = (typeof TextVerbosities)[number] | (string & {})

packages/ai/src/protocols/utils/responses-compaction.ts

@@ -11,6 +11,7 @@ import {
   mergeJsonRecords,
 } from "../../schema/index.js"
 import type { CompactOperation } from "../../route/client.js"
+import { stripEffortUpdates } from "../../effort-updates.js"
 import { Endpoint } from "../../route/endpoint.js"
 import { RequestExecutor } from "../../route/executor.js"
 import { HttpTransport } from "../../route/transport/index.js"
@@ -75,7 +76,8 @@ const Response = Schema.Struct({
 export const make = (adapter: OpenResponses.ProviderAdapter): CompactOperation =>
   Effect.fn("ResponsesCompaction.execute")(function* (request, executor, options) {
     const route = request.model.route
-    const native = yield* OpenResponses.lowerConversation(request, adapter)
+    // The standalone compaction endpoint rejects histories containing configuration updates.
+    const native = yield* OpenResponses.lowerConversation(stripEffortUpdates(request), adapter)
     const body = yield* ProviderShared.validateWith(Schema.decodeUnknownEffect(Body))(
       mergeJsonRecords(
         {

packages/ai/src/providers/alibaba.ts

@@ -6,7 +6,7 @@ import { AuthOptions, type AtLeastOne, type ProviderAuthOption } from "../route/
 import { Route, type RouteDefaultsInput } from "../route/client.js"
 import { Endpoint } from "../route/endpoint.js"
 import { Framing } from "../route/framing.js"
-import { ProviderID, ToolDefinition, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, ToolDefinition, type ModelID } from "../schema/index.js"
 
 export const id = ProviderID.make("alibaba")
 
@@ -82,8 +82,13 @@ export const configure = (input: Config) => {
         ? hosts.get(region)
         : `${workspaceID}.${region}.maas.aliyuncs.com`
   if (baseURL === undefined) {
-    if (region === undefined) throw new Error("Alibaba requires region or baseURL")
-    if (host === undefined) throw new Error(`Alibaba region ${region} requires workspaceID or baseURL`)
+    if (region === undefined)
+      throw new ProviderConfigurationError({ provider: id, message: "Alibaba requires region or baseURL" })
+    if (host === undefined)
+      throw new ProviderConfigurationError({
+        provider: id,
+        message: `Alibaba region ${region} requires workspaceID or baseURL`,
+      })
   }
   const opts = { ...rest, auth: AuthOptions.bearer(input, ["DASHSCOPE_API_KEY", "ALIBABA_API_KEY"]) }
   const common = { ...opts, endpoint: { baseURL: baseURL ?? `https://${host}/compatible-mode/v1` } }

packages/ai/src/providers/amazon-bedrock-mantle.ts

@@ -4,7 +4,7 @@ import type { ProviderPackage } from "../provider-package.js"
 import { OpenAIChat } from "../protocols/openai-chat.js"
 import { OpenResponses } from "../protocols/open-responses.js"
 import { BedrockAuth, type Credentials } from "../protocols/utils/bedrock-auth.js"
-import { ProviderID, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type ModelID } from "../schema/index.js"
 import { withOpenAIOptions, type OpenAIProviderOptionsInput } from "./openai-options.js"
 
 export const id = ProviderID.make("amazon-bedrock")
@@ -79,9 +79,12 @@ const defaults = (input: Config) => {
 
 export const configure = (input: Config = {}) => {
   if (input.auth === "bearer" && input.apiKey === undefined && process.env.AWS_BEARER_TOKEN_BEDROCK === undefined)
-    throw new Error("Amazon Bedrock Mantle bearer auth requires apiKey")
+    throw new ProviderConfigurationError({ provider: id, message: "Amazon Bedrock Mantle bearer auth requires apiKey" })
   if (input.auth === "sigv4" && input.apiKey !== undefined)
-    throw new Error("Amazon Bedrock Mantle SigV4 auth does not accept apiKey")
+    throw new ProviderConfigurationError({
+      provider: id,
+      message: "Amazon Bedrock Mantle SigV4 auth does not accept apiKey",
+    })
   const configuredResponsesRoute = configuredRoute(responsesRoute, input)
   const configuredChatRoute = configuredRoute(chatRoute, input)
   const modelDefaults = defaults(input)

packages/ai/src/providers/amazon-bedrock.ts

@@ -1,6 +1,6 @@
 import type { RouteDefaultsInput } from "../route/client.js"
 import type { ProviderPackage } from "../provider-package.js"
-import { ProviderID, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type ModelID } from "../schema/index.js"
 import * as BedrockConverse from "../protocols/bedrock-converse.js"
 import type { BedrockCredentials } from "../protocols/bedrock-converse.js"
 import { BedrockAuth } from "../protocols/utils/bedrock-auth.js"
@@ -39,8 +39,9 @@ const bedrockBaseURL = (region: string) => `https://bedrock-runtime.${region}.am
 const configuredRoute = (input: Config) => {
   const { apiKey, auth, credentials, profile, region, baseURL, ...rest } = input
   if (auth === "bearer" && apiKey === undefined && process.env.AWS_BEARER_TOKEN_BEDROCK === undefined)
-    throw new Error("Amazon Bedrock bearer auth requires apiKey")
-  if (auth === "sigv4" && apiKey !== undefined) throw new Error("Amazon Bedrock SigV4 auth does not accept apiKey")
+    throw new ProviderConfigurationError({ provider: id, message: "Amazon Bedrock bearer auth requires apiKey" })
+  if (auth === "sigv4" && apiKey !== undefined)
+    throw new ProviderConfigurationError({ provider: id, message: "Amazon Bedrock SigV4 auth does not accept apiKey" })
   const resolvedRegion = BedrockAuth.resolveRegion(input)
   return BedrockConverse.route.with({
     ...rest,

packages/ai/src/providers/anthropic-compatible.ts

@@ -3,7 +3,7 @@ import { AnthropicMessages } from "../protocols/anthropic-messages.js"
 import { Auth } from "../route/auth.js"
 import type { ProviderAuthOption } from "../route/auth-options.js"
 import type { RouteDefaultsInput } from "../route/client.js"
-import { ProviderID, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type ModelID } from "../schema/index.js"
 
 export type AnthropicOptionsInput = AnthropicMessages.OptionsInput
 export type AnthropicProviderOptionsInput = AnthropicMessages.ProviderOptionsInput
@@ -36,8 +36,12 @@ const auth = (input: ProviderAuthOption<"optional">) => {
 }
 
 export const configure = (input: Config) => {
-  if (!input.baseURL) throw new Error("Anthropic-compatible providers require a baseURL")
   const provider = input.provider ?? "anthropic-compatible"
+  if (!input.baseURL)
+    throw new ProviderConfigurationError({
+      provider: ProviderID.make(provider),
+      message: "Anthropic-compatible providers require a baseURL",
+    })
   const { provider: _, baseURL, apiKey: _apiKey, auth: _auth, ...rest } = input
   const route = AnthropicMessages.route.with({
     ...rest,
@@ -61,8 +65,13 @@ export const model: ProviderPackage.Definition<Settings, AnthropicMessages.Provi
   modelID,
   settings,
 ) => {
+  // Read before the exclusivity check narrows a conflicting settings object to `never`.
+  const provider = ProviderID.make(settings.provider ?? id)
   if (settings.apiKey !== undefined && settings.authToken !== undefined)
-    throw new Error("Anthropic-compatible apiKey cannot be combined with authToken")
+    throw new ProviderConfigurationError({
+      provider,
+      message: "Anthropic-compatible apiKey cannot be combined with authToken",
+    })
   return configure({
     ...(settings.authToken === undefined ? { apiKey: settings.apiKey } : { auth: Auth.bearer(settings.authToken) }),
     baseURL: settings.baseURL,

packages/ai/src/providers/anthropic.ts

@@ -2,7 +2,7 @@ import type { RouteDefaultsInput } from "../route/client.js"
 import { Auth } from "../route/auth.js"
 import type { ProviderAuthOption } from "../route/auth-options.js"
 import type { ProviderPackage } from "../provider-package.js"
-import { ProviderID, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type ModelID } from "../schema/index.js"
 import { AnthropicMessages } from "../protocols/anthropic-messages.js"
 import { AnthropicCompatible } from "./anthropic-compatible.js"
 
@@ -57,7 +57,10 @@ export const model: ProviderPackage.Definition<Settings, AnthropicMessages.Provi
   settings,
 ) => {
   if (settings.apiKey !== undefined && settings.authToken !== undefined)
-    throw new Error("Anthropic apiKey cannot be combined with authToken")
+    throw new ProviderConfigurationError({
+      provider: id,
+      message: "Anthropic apiKey cannot be combined with authToken",
+    })
   return configure({
     ...(settings.authToken === undefined ? { apiKey: settings.apiKey } : { auth: Auth.bearer(settings.authToken) }),
     baseURL: settings.baseURL,

packages/ai/src/providers/azure.ts

@@ -3,7 +3,7 @@ import { Auth } from "../route/auth.js"
 import { type AtLeastOne, type ProviderAuthOption } from "../route/auth-options.js"
 import type { Route, RouteDefaultsInput, CompactionOperations } from "../route/client.js"
 import type { ProviderPackage } from "../provider-package.js"
-import { ProviderID, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type ModelID } from "../schema/index.js"
 import * as OpenAIChat from "../protocols/openai-chat.js"
 import * as OpenAIResponses from "../protocols/openai-responses.js"
 import { ProviderShared } from "../protocols/shared.js"
@@ -163,7 +163,7 @@ const config = (settings: Settings): Config => {
   }
   if (settings.baseURL !== undefined) return { ...common, baseURL: settings.baseURL }
   if (settings.resourceName !== undefined) return { ...common, resourceName: settings.resourceName }
-  throw new Error("Azure requires resourceName or baseURL")
+  throw new ProviderConfigurationError({ provider: id, message: "Azure requires resourceName or baseURL" })
 }
 
 export const responsesModel: ProviderPackage.Definition<

packages/ai/src/providers/cloudflare-ai-gateway.ts

@@ -5,7 +5,7 @@ import { Auth } from "../route/auth.js"
 import type { AtLeastOne, ProviderAuthOption } from "../route/auth-options.js"
 import { Route, type RouteDefaultsInput } from "../route/client.js"
 import { Endpoint } from "../route/endpoint.js"
-import { ProviderID, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type ModelID } from "../schema/index.js"
 import type { OpenAIProviderOptionsInput } from "./openai-options.js"
 
 export const id = ProviderID.make("cloudflare-ai-gateway")
@@ -35,7 +35,11 @@ export type Settings = ProviderPackage.Settings &
 
 export const baseURL = (input: GatewayURL) => {
   if (input.baseURL) return input.baseURL
-  if (!input.accountId) throw new Error("CloudflareAIGateway.configure requires accountId unless baseURL is supplied")
+  if (!input.accountId)
+    throw new ProviderConfigurationError({
+      provider: id,
+      message: "CloudflareAIGateway.configure requires accountId unless baseURL is supplied",
+    })
   return `https://gateway.ai.cloudflare.com/v1/${encodeURIComponent(input.accountId)}/${encodeURIComponent(input.gatewayId?.trim() || "default")}/compat`
 }
 

packages/ai/src/providers/cloudflare-workers-ai.ts

@@ -3,7 +3,7 @@ import { OpenAIChat } from "../protocols/openai-chat.js"
 import { AuthOptions, type AtLeastOne, type ProviderAuthOption } from "../route/auth-options.js"
 import { Route, type RouteDefaultsInput } from "../route/client.js"
 import { Endpoint } from "../route/endpoint.js"
-import { ProviderID, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type ModelID } from "../schema/index.js"
 import type { OpenAIProviderOptionsInput } from "./openai-options.js"
 
 export const id = ProviderID.make("cloudflare-workers-ai")
@@ -28,7 +28,11 @@ export type Settings = ProviderPackage.Settings &
 
 export const baseURL = (input: WorkersAIURL) => {
   if (input.baseURL) return input.baseURL
-  if (!input.accountId) throw new Error("CloudflareWorkersAI.configure requires accountId unless baseURL is supplied")
+  if (!input.accountId)
+    throw new ProviderConfigurationError({
+      provider: id,
+      message: "CloudflareWorkersAI.configure requires accountId unless baseURL is supplied",
+    })
   return `https://api.cloudflare.com/client/v4/accounts/${encodeURIComponent(input.accountId)}/ai/v1`
 }
 

packages/ai/src/providers/google-vertex-chat.ts

@@ -2,7 +2,7 @@ import type { ProviderPackage } from "../provider-package.js"
 import { OpenAIChat } from "../protocols/openai-chat.js"
 import { Route, type RouteDefaultsInput } from "../route/client.js"
 import { Endpoint } from "../route/endpoint.js"
-import { ProviderID, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type ModelID } from "../schema/index.js"
 import { GoogleVertexShared } from "./google-vertex-shared.js"
 import type { OpenAIProviderOptionsInput } from "./openai-options.js"
 
@@ -37,7 +37,8 @@ const route = Route.make({
 export const routes = [route]
 
 const configuredRoute = (input: Config) => {
-  if ("apiKey" in input && input.apiKey !== undefined) throw new Error("Google Vertex Chat does not support API keys")
+  if ("apiKey" in input && input.apiKey !== undefined)
+    throw new ProviderConfigurationError({ provider: id, message: "Google Vertex Chat does not support API keys" })
   const {
     accessToken: _accessToken,
     auth: _auth,
@@ -74,7 +75,8 @@ export const provider = {
 }
 
 export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) => {
-  if (settings.apiKey !== undefined) throw new Error("Google Vertex Chat does not support API keys")
+  if (settings.apiKey !== undefined)
+    throw new ProviderConfigurationError({ provider: id, message: "Google Vertex Chat does not support API keys" })
   return configure({
     accessToken: settings.accessToken,
     baseURL: settings.baseURL,

packages/ai/src/providers/google-vertex-messages.ts

@@ -5,7 +5,7 @@ import { Auth } from "../route/auth.js"
 import { Route, type RouteDefaultsInput } from "../route/client.js"
 import { Endpoint } from "../route/endpoint.js"
 import { Protocol } from "../route/protocol.js"
-import { ProviderID, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type ModelID } from "../schema/index.js"
 import { GoogleVertexShared } from "./google-vertex-shared.js"
 
 export type AnthropicOptionsInput = AnthropicMessages.OptionsInput
@@ -67,7 +67,7 @@ export const routes = [route]
 
 const configuredRoute = (input: Config) => {
   if ("apiKey" in input && input.apiKey !== undefined)
-    throw new Error("Google Vertex Messages does not support API keys")
+    throw new ProviderConfigurationError({ provider: id, message: "Google Vertex Messages does not support API keys" })
   const {
     accessToken: _accessToken,
     auth: _auth,
@@ -107,7 +107,8 @@ export const model: ProviderPackage.Definition<Settings, AnthropicMessages.Provi
   modelID,
   settings,
 ) => {
-  if (settings.apiKey !== undefined) throw new Error("Google Vertex Messages does not support API keys")
+  if (settings.apiKey !== undefined)
+    throw new ProviderConfigurationError({ provider: id, message: "Google Vertex Messages does not support API keys" })
   return configure({
     accessToken: settings.accessToken,
     baseURL: settings.baseURL,

packages/ai/src/providers/google-vertex-responses.ts

@@ -2,7 +2,7 @@ import type { ProviderPackage } from "../provider-package.js"
 import { OpenResponses } from "../protocols/open-responses.js"
 import { Route, type RouteDefaultsInput } from "../route/client.js"
 import { Endpoint } from "../route/endpoint.js"
-import { ProviderID, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type ModelID } from "../schema/index.js"
 import { GoogleVertexShared } from "./google-vertex-shared.js"
 import type { OpenResponsesProviderOptionsInput } from "./open-responses-options.js"
 
@@ -39,7 +39,7 @@ export const routes = [route]
 
 const configuredRoute = (input: Config) => {
   if ("apiKey" in input && input.apiKey !== undefined)
-    throw new Error("Google Vertex Responses does not support API keys")
+    throw new ProviderConfigurationError({ provider: id, message: "Google Vertex Responses does not support API keys" })
   const {
     accessToken: _accessToken,
     auth: _auth,
@@ -79,7 +79,8 @@ export const model: ProviderPackage.Definition<Settings, OpenResponsesProviderOp
   modelID,
   settings,
 ) => {
-  if (settings.apiKey !== undefined) throw new Error("Google Vertex Responses does not support API keys")
+  if (settings.apiKey !== undefined)
+    throw new ProviderConfigurationError({ provider: id, message: "Google Vertex Responses does not support API keys" })
   return configure({
     accessToken: settings.accessToken,
     baseURL: settings.baseURL,

packages/ai/src/providers/google-vertex-shared.ts

@@ -1,8 +1,10 @@
 import type { AnyAuthClient } from "google-auth-library"
 import { Effect, Redacted } from "effect"
 import { Auth, MissingCredentialError } from "../route/auth.js"
+import { ProviderConfigurationError, ProviderID } from "../schema/index.js"
 
 const SCOPE = "https://www.googleapis.com/auth/cloud-platform"
+const id = ProviderID.make("google-vertex")
 
 export type OAuthOptions =
   | { readonly accessToken?: string; readonly auth?: never }
@@ -35,12 +37,18 @@ export const host = (location: string) => {
 
 export const requireProject = (value: string | undefined) => {
   if (value) return value
-  throw new Error("Google Vertex requires a project when baseURL is not configured")
+  throw new ProviderConfigurationError({
+    provider: id,
+    message: "Google Vertex requires a project when baseURL is not configured",
+  })
 }
 
 export const apiKey = (input: ApiKeyOptions) => {
   if (input.apiKey !== undefined && (input.accessToken !== undefined || input.auth !== undefined))
-    throw new Error("Google Vertex apiKey cannot be combined with accessToken or auth")
+    throw new ProviderConfigurationError({
+      provider: id,
+      message: "Google Vertex apiKey cannot be combined with accessToken or auth",
+    })
   if (input.accessToken !== undefined || input.auth !== undefined) return undefined
   return input.apiKey ?? process.env.GOOGLE_VERTEX_API_KEY
 }
@@ -68,7 +76,10 @@ const adc = (project?: string) => {
 
 export const oauth = (input: OAuthOptions, project?: string) => {
   if (input.accessToken !== undefined && input.auth !== undefined)
-    throw new Error("Google Vertex accessToken cannot be combined with auth")
+    throw new ProviderConfigurationError({
+      provider: id,
+      message: "Google Vertex accessToken cannot be combined with auth",
+    })
   if (input.auth) return input.auth
   if (input.accessToken !== undefined) return Auth.bearer(input.accessToken)
   return adc(project)

packages/ai/src/providers/google-vertex.ts

@@ -6,7 +6,7 @@ import { Auth } from "../route/auth.js"
 import { Route, type RouteDefaultsInput } from "../route/client.js"
 import { Endpoint } from "../route/endpoint.js"
 import { Framing } from "../route/framing.js"
-import { ProviderID, type LLMRequest, type ModelID } from "../schema/index.js"
+import { ProviderConfigurationError, ProviderID, type LLMRequest, type ModelID } from "../schema/index.js"
 import { GoogleVertexShared } from "./google-vertex-shared.js"
 
 export interface GeminiOptionsInput extends Gemini.OptionsInput {
@@ -93,7 +93,10 @@ const configuredRoute = (input: Config, modelID: string | ModelID) => {
   const apiKey = GoogleVertexShared.apiKey(input)
   const endpointModel = String(modelID).startsWith("endpoints/")
   if (apiKey !== undefined && endpointModel)
-    throw new Error("Google Vertex tuned models do not support Express Mode API keys")
+    throw new ProviderConfigurationError({
+      provider: id,
+      message: "Google Vertex tuned models do not support Express Mode API keys",
+    })
   const location = GoogleVertexShared.location(inputLocation, "us-central1")
   const project = GoogleVertexShared.project(inputProject)
   const endpoint =
@@ -123,7 +126,10 @@ export const provider = {
 }
 export const model: ProviderPackage.Definition<Settings, GeminiProviderOptionsInput>["model"] = (modelID, settings) => {
   if (settings.apiKey !== undefined && settings.accessToken !== undefined)
-    throw new Error("Google Vertex apiKey cannot be combined with accessToken or auth")
+    throw new ProviderConfigurationError({
+      provider: id,
+      message: "Google Vertex apiKey cannot be combined with accessToken or auth",
+    })
   return configure({
     ...(settings.apiKey === undefined ? { accessToken: settings.accessToken } : { apiKey: settings.apiKey }),
     baseURL: settings.baseURL,

packages/ai/src/providers/xai.ts

@@ -41,6 +41,10 @@ const responsesRoute = Route.make({
     id: "openai-responses",
     name: "xAI Responses",
     rotateAfterMs: RESPONSES_WEBSOCKET_ROTATE_AFTER_MS,
+    // xAI continues a chain only from stored responses: with `store: false` (the route default) `previous_response_id`
+    // fails with "Response with id=… not found", so those steps are sent in full over the reused connection. It also
+    // rejects `instructions` next to `previous_response_id` and keeps the instructions of the response it continues.
+    continuation: ({ instructions: _instructions, ...request }) => (request.store === false ? undefined : request),
   }),
   defaults: { providerOptions: { store: false, include: ["reasoning.encrypted_content"] } },
 })

packages/ai/src/route/client.ts

@@ -7,6 +7,7 @@ import { HttpTransport } from "./transport/index.js"
 import type { HttpMiddleware, Transport, TransportRuntime, WebSocketChannelExecutor } from "./transport/index.js"
 import type { Protocol } from "./protocol.js"
 import { applyCachePolicy } from "../cache-policy.js"
+import { applyEffortUpdates } from "../effort-updates.js"
 import { normalizeToolHistory } from "../tool-history.js"
 import { sanitizeSurrogates } from "../utils/sanitize.js"
 import * as ProviderShared from "../protocols/shared.js"
@@ -23,6 +24,7 @@ import {
   LanguageModel,
   LLMEvent,
   InvalidProviderOutputError,
+  ProviderConfigurationError,
   ProviderID,
   mergeGenerationOptions,
   mergeHttpOptions,
@@ -54,6 +56,7 @@ export interface Route<
   readonly transport: Transport<Body, Prepared, unknown>
   readonly defaults: RouteDefaults
   readonly body: RouteBody<Body>
+  readonly supportsEffortUpdates?: (request: LLMRequest) => boolean
   readonly with: {
     <Next extends CompactionOperations | undefined>(
       patch: RoutePatch<Body, Prepared> & { readonly compact: Next },
@@ -128,7 +131,10 @@ const makeRouteLanguageModel = <Options extends ProviderOptions, Compact extends
   const provider = route.provider ?? ("provider" in mapped ? mapped.provider : undefined)
   if (!provider) throw new Error(`Route.model(${route.id}) requires a provider`)
   if (!endpointBaseURL(route.endpoint))
-    throw new Error(`Route.model(${route.id}) requires an endpoint baseURL — configure it on the route first`)
+    throw new ProviderConfigurationError({
+      provider: ProviderID.make(provider),
+      message: `Route.model(${route.id}) requires an endpoint baseURL — configure it on the route first`,
+    })
   return LanguageModel.make<Options, Compact>({
     ...mapped,
     provider,
@@ -384,6 +390,7 @@ function makeFromTransport<Body, Prepared, Frame, Event, State>(
       transport: routeInput.transport,
       defaults: routeInput.defaults ?? {},
       body: protocol.body,
+      supportsEffortUpdates: protocol.supportsEffortUpdates,
       with: (patch: RoutePatch<Body, Prepared>) => {
         const { compact, id, provider, providerMetadataKey, auth, transport, endpoint, ...defaults } = patch
         return build({
@@ -554,7 +561,9 @@ const prepareRequest = (request: LLMRequest) => {
     [...new Map(tools.map((tool) => [`${tool.type}:${tool.name}`, tool])).values()].map((tool) =>
       tool.type === "tool" ? tool : { ...tool, tools: dedupe(tool.tools) },
     )
-  const resolved = applyCachePolicy(LLMRequest.update(sanitized, { tools: dedupe(sanitized.tools) }))
+  const resolved = applyCachePolicy(
+    applyEffortUpdates(LLMRequest.update(sanitized, { tools: dedupe(sanitized.tools) })),
+  )
   const headers = resolved.model.route.headers?.({ request: resolved })
   return headers === undefined
     ? resolved

packages/ai/src/route/protocol.ts

@@ -41,6 +41,8 @@ export interface Protocol<Body, Frame, Event, State> {
   readonly body: ProtocolBody<Body>
   /** Response side: streaming state machine. */
   readonly stream: ProtocolStream<Frame, Event, State>
+  /** Whether `body.from` lowers `Message.effort(...)` markers; wrappers around another `body.from` must forward it. */
+  readonly supportsEffortUpdates?: (request: LLMRequest) => boolean
 }
 
 export interface ProtocolBody<Body> {

packages/ai/src/schema/errors.ts

@@ -50,6 +50,19 @@ export class UnsupportedOperationError extends Schema.TaggedError<UnsupportedOpe
   route: Schema.optional(RouteID),
 }) {}
 
+/**
+ * Provider settings that are missing, conflicting, or unsupported, such as
+ * Azure without `resourceName` or `baseURL`. Thrown synchronously while a
+ * provider facade or package entrypoint configures a model, before any
+ * request exists, so it is not an `AIError` reason.
+ */
+export class ProviderConfigurationError extends Schema.TaggedError<ProviderConfigurationError>(
+  "AI.Error.ProviderConfiguration",
+)("ProviderConfiguration", {
+  provider: ProviderID,
+  message: Schema.String,
+}) {}
+
 export class NoRouteError extends Schema.TaggedError<NoRouteError>("AI.Error.NoRoute")("NoRoute", {
   ...ReasonFields,
   route: RouteID,

packages/ai/src/schema/messages.ts

@@ -9,6 +9,7 @@ import {
   LanguageModelSchema,
   type LanguageModel,
   ProviderOptions,
+  ReasoningEffort,
 } from "./options.js"
 import { ProviderID } from "./ids.js"
 
@@ -217,6 +218,14 @@ export const CompactionPart = Object.assign(compactionPartSchema, {
     Schema.decodeUnknownSync(compactionPartSchema)({ type: "compaction", ...input }),
 })
 
+/** Reasoning effort changed here, from `previous` to `effort`; `undefined` is the model default. */
+export const EffortPart = Schema.Struct({
+  type: Schema.Literal("effort"),
+  effort: Schema.optional(ReasoningEffort),
+  previous: Schema.optional(ReasoningEffort),
+}).annotate({ identifier: "LLM.Content.Effort" })
+export type EffortPart = Schema.Schema.Type<typeof EffortPart>
+
 export const ContentPart = Schema.Union([
   TextPart,
   MediaPart,
@@ -224,6 +233,7 @@ export const ContentPart = Schema.Union([
   ToolResultPart,
   ReasoningPart,
   CompactionPart,
+  EffortPart,
 ]).pipe(Schema.toTaggedUnion("type"))
 export type ContentPart = Schema.Schema.Type<typeof ContentPart>
 
@@ -265,6 +275,9 @@ export namespace Message {
    */
   export const system = (content: SystemContentInput) => make({ role: "system", content })
 
+  export const effort = (input: { readonly effort?: ReasoningEffort; readonly previous?: ReasoningEffort }) =>
+    make({ role: "system", content: [{ type: "effort", effort: input.effort, previous: input.previous }] })
+
   export const tool = (result: ToolResultPart | Parameters<typeof ToolResultPart.make>[0]) =>
     make({ role: "tool", content: ["type" in result ? result : ToolResultPart.make(result)] })
 }

packages/ai/src/schema/options.ts

@@ -140,6 +140,14 @@ export namespace LanguageModelDefaults {
   }
 }
 
+/** Ordered lowest to highest. */
+export const ReasoningEfforts = ["none", "minimal", "low", "medium", "high", "xhigh", "max"] as const
+export type ReasoningEffort = (typeof ReasoningEfforts)[number] | (string & {})
+export const ReasoningEffort = Schema.declare<ReasoningEffort>(
+  (value): value is ReasoningEffort => typeof value === "string",
+  { title: "ReasoningEffort" },
+)
+
 export const LanguageModelToolSchemaCompatibility = Schema.Literals(["gemini", "moonshot"])
 export type LanguageModelToolSchemaCompatibility = Schema.Schema.Type<typeof LanguageModelToolSchemaCompatibility>
 
@@ -165,6 +173,8 @@ export class LanguageModelCompatibility extends Schema.Class<LanguageModelCompat
   requireSignature: Schema.optional(Schema.Boolean),
   /** Supports Anthropic's thinking-prefix mismatch controls. Overrides model-ID detection. */
   supportsThinkingBlockBinding: Schema.optional(Schema.Boolean),
+  /** Supports per-message effort updates. Overrides model-ID detection. */
+  supportsEffortUpdates: Schema.optional(Schema.Boolean),
 }) {}
 
 export namespace LanguageModelCompatibility {

packages/ai/test/effort-updates.test.ts

@@ -0,0 +1,439 @@
+import { describe, expect, test } from "bun:test"
+import { Effect } from "effect"
+import { LLM, LLMRequest, Message, ToolCallPart } from "../src/index.js"
+import { Auth, LLMClient } from "../src/route.js"
+import { compileRequest } from "../src/route/client.js"
+import { AnthropicMessages } from "../src/protocols/anthropic-messages.js"
+import { OpenAIResponses } from "../src/protocols/openai-responses.js"
+import { Gemini } from "../src/protocols/gemini.js"
+import { GoogleVertexMessages, OpenAI } from "../src/providers.js"
+import { applyCachePolicy } from "../src/cache-policy.js"
+import { applyEffortUpdates } from "../src/effort-updates.js"
+import { it, testEffect } from "./lib/effect.js"
+import { dynamicResponse } from "./lib/http.js"
+import { sseEvents } from "./lib/sse.js"
+
+const anthropic = (id: string, compatibility?: { readonly supportsEffortUpdates?: boolean }) =>
+  AnthropicMessages.route
+    .with({ endpoint: { baseURL: "https://api.anthropic.test/v1/" }, auth: Auth.header("x-api-key", "test") })
+    .model({ id, compatibility })
+
+const openai = (id: string, compatibility?: { readonly supportsEffortUpdates?: boolean }) =>
+  OpenAIResponses.route
+    .with({ endpoint: { baseURL: "https://api.openai.test/v1/" }, auth: Auth.bearer("test") })
+    .model({ id, compatibility })
+
+const opus5 = anthropic("claude-opus-5")
+const astra = openai("gpt-6-astra")
+
+const lowFromHigh = Message.effort({ effort: "low", previous: "high" })
+const conversation = [Message.user("Before."), lowFromHigh, Message.user("After.")]
+
+const systemMessages = (body: AnthropicMessages.AnthropicMessagesBody) =>
+  body.messages.filter((message) => message.role === "system")
+
+const updates = (body: OpenAIResponses.OpenAIResponsesBody) =>
+  body.input.filter((item) => "type" in item && item.type === "configuration_update")
+
+describe("applyEffortUpdates", () => {
+  test("keeps the request identity without markers and for protocols that lower them", () => {
+    const plain = LLM.request({ model: opus5, prompt: "hi" })
+    expect(applyEffortUpdates(plain)).toBe(plain)
+
+    const supported = LLM.request({ model: opus5, messages: conversation, providerOptions: { effort: "low" } })
+    expect(applyEffortUpdates(supported)).toBe(supported)
+  })
+
+  it.effect("compiles markers away for protocols without per-message effort", () =>
+    Effect.gen(function* () {
+      const model = Gemini.route
+        .with({
+          endpoint: { baseURL: "https://generativelanguage.test/v1beta/" },
+          auth: Auth.header("x-goog-api-key", "test"),
+        })
+        .model({ id: "gemini-3.5-flash" })
+      const withMarkers = yield* compileRequest(LLM.request({ model, messages: conversation }))
+      const withoutMarkers = yield* compileRequest(
+        LLM.request({ model, messages: [Message.user("Before."), Message.user("After.")] }),
+      )
+
+      expect(withMarkers.body).toEqual(withoutMarkers.body)
+    }),
+  )
+})
+
+describe("cache policy", () => {
+  it.effect("walks the tail breakpoint back past a trailing effort marker", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model: opus5,
+          messages: [Message.user("first"), Message.assistant("reply"), Message.user("latest"), lowFromHigh],
+          providerOptions: { effort: "low" },
+          cache: "auto",
+        }),
+      )
+
+      expect(prepared.body.messages).toEqual([
+        { role: "user", content: [{ type: "text", text: "first" }] },
+        { role: "assistant", content: [{ type: "text", text: "reply" }] },
+        { role: "user", content: [{ type: "text", text: "latest", cache_control: { type: "ephemeral" } }] },
+        { role: "system", content: [], output_config: { effort: "low" } },
+      ])
+    }),
+  )
+})
+
+describe("Anthropic Messages effort updates", () => {
+  it.effect("lowers markers to per-turn system messages and freezes the top-level effort", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({ model: opus5, messages: conversation, providerOptions: { effort: "low" }, cache: "none" }),
+      )
+
+      expect(prepared.body.output_config).toEqual({ effort: "high" })
+      expect(prepared.body.messages).toEqual([
+        { role: "user", content: [{ type: "text", text: "Before." }] },
+        { role: "system", content: [], output_config: { effort: "low" } },
+        { role: "user", content: [{ type: "text", text: "After." }] },
+      ])
+    }),
+  )
+
+  it.effect("omits the frozen effort for the model default and sends `high` for a switch back to it", () =>
+    Effect.gen(function* () {
+      const format = { type: "json_schema" as const, schema: { type: "object" } }
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model: opus5,
+          messages: [
+            Message.user("One."),
+            Message.effort({ effort: "low" }),
+            Message.user("Two."),
+            Message.effort({ previous: "low" }),
+            Message.user("Three."),
+          ],
+          providerOptions: { output_config: { format } },
+          cache: "none",
+        }),
+      )
+
+      expect(prepared.body.output_config).toEqual({ format })
+      expect(systemMessages(prepared.body)).toEqual([
+        { role: "system", content: [], output_config: { effort: "low" } },
+        { role: "system", content: [], output_config: { effort: "high" } },
+      ])
+    }),
+  )
+
+  it.effect("requests the mid-conversation output config beta only when markers are sent", () =>
+    Effect.gen(function* () {
+      for (const [model, betas] of [
+        [opus5, "existing-beta,mid-conversation-output-config-2026-07-01"],
+        [anthropic("claude-sonnet-5"), "existing-beta"],
+      ] as const) {
+        const request = LLM.request({
+          model,
+          messages: conversation,
+          providerOptions: { effort: "low" },
+          http: { headers: { "anthropic-beta": "existing-beta" } },
+        })
+        const compiled = yield* compileRequest(request)
+        const prepared = yield* AnthropicMessages.route.prepareTransport(compiled.body, request)
+        expect(prepared.request.headers["anthropic-beta"]).toBe(betas)
+      }
+    }),
+  )
+
+  it.effect("accepts a marker between a tool call and its result", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model: opus5,
+          messages: [
+            Message.user("Weather?"),
+            Message.assistant([ToolCallPart.make({ id: "call_1", name: "lookup", input: {} })]),
+            lowFromHigh,
+            Message.tool({ id: "call_1", name: "lookup", result: { temp: 72 } }),
+          ],
+          providerOptions: { effort: "low" },
+          cache: "none",
+        }),
+      )
+
+      expect(prepared.body.messages).toEqual([
+        { role: "user", content: [{ type: "text", text: "Weather?" }] },
+        { role: "assistant", content: [{ type: "tool_use", id: "call_1", name: "lookup", input: {} }] },
+        { role: "system", content: [], output_config: { effort: "low" } },
+        { role: "user", content: [{ type: "tool_result", tool_use_id: "call_1", content: '{"temp":72}' }] },
+      ])
+    }),
+  )
+
+  it.effect("falls back to a plain top-level effort when history drifted from the current effort", () =>
+    Effect.gen(function* () {
+      const drifted = yield* compileRequest(
+        LLM.request({ model: opus5, messages: conversation, providerOptions: { effort: "medium" }, cache: "none" }),
+      )
+      const plain = yield* compileRequest(
+        LLM.request({
+          model: opus5,
+          messages: [Message.user("Before."), Message.user("After.")],
+          providerOptions: { effort: "medium" },
+          cache: "none",
+        }),
+      )
+
+      expect(drifted.body).toEqual(plain.body)
+      expect(drifted.body.output_config).toEqual({ effort: "medium" })
+    }),
+  )
+
+  for (const [id, supported] of [
+    ["claude-opus-5", true],
+    ["claude-opus-5-20260901", true],
+    ["anthropic/claude-opus-5", true],
+    ["claude-fable-5-1", true],
+    ["claude-mythos-5-1", true],
+    ["claude-fable-5", false],
+    ["claude-opus-4-8", false],
+    ["claude-sonnet-5", false],
+    ["kimi-k2.5", false],
+  ] as const) {
+    it.effect(`${supported ? "lowers" : "strips"} markers for ${id}`, () =>
+      Effect.gen(function* () {
+        const prepared = yield* compileRequest(
+          LLM.request({ model: anthropic(id), messages: conversation, providerOptions: { effort: "low" } }),
+        )
+
+        expect(systemMessages(prepared.body)).toHaveLength(supported ? 1 : 0)
+        expect(prepared.body.output_config).toEqual({ effort: supported ? "high" : "low" })
+      }),
+    )
+  }
+
+  it.effect("honors the compatibility override in both directions", () =>
+    Effect.gen(function* () {
+      const enabled = yield* compileRequest(
+        LLM.request({
+          model: anthropic("claude-sonnet-5", { supportsEffortUpdates: true }),
+          messages: conversation,
+          providerOptions: { effort: "low" },
+        }),
+      )
+      const disabled = yield* compileRequest(
+        LLM.request({
+          model: anthropic("claude-opus-5", { supportsEffortUpdates: false }),
+          messages: conversation,
+          providerOptions: { effort: "low" },
+        }),
+      )
+
+      expect(systemMessages(enabled.body)).toHaveLength(1)
+      expect(systemMessages(disabled.body)).toHaveLength(0)
+    }),
+  )
+
+  it.effect("strips markers on the Vertex Anthropic route, whose protocol wrapper does not forward support", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model: GoogleVertexMessages.configure({ accessToken: "test", location: "global", project: "test" }).model(
+            "claude-opus-5",
+          ),
+          messages: conversation,
+          providerOptions: { effort: "low" },
+        }),
+      )
+
+      expect(systemMessages(prepared.body)).toHaveLength(0)
+      expect(prepared.body.output_config).toEqual({ effort: "low" })
+    }),
+  )
+})
+
+describe("OpenAI Responses effort updates", () => {
+  it.effect("lowers markers to configuration_update items and freezes reasoning.effort", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({ model: astra, messages: conversation, providerOptions: { reasoningEffort: "low" } }),
+      )
+
+      expect(prepared.body.reasoning).toEqual({ effort: "high" })
+      expect(prepared.body.input).toEqual([
+        { role: "user", content: [{ type: "input_text", text: "Before." }] },
+        { type: "configuration_update", reasoning: { effort: "low" } },
+        { role: "user", content: [{ type: "input_text", text: "After." }] },
+      ])
+    }),
+  )
+
+  it.effect("coalesces consecutive updates so the newest wins", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model: astra,
+          messages: [
+            Message.user("Before."),
+            Message.effort({ effort: "low", previous: "medium" }),
+            Message.effort({ effort: "xhigh", previous: "low" }),
+            Message.user("After."),
+          ],
+          providerOptions: { reasoningEffort: "xhigh" },
+        }),
+      )
+
+      expect(prepared.body.reasoning).toEqual({ effort: "medium" })
+      expect(prepared.body.input).toEqual([
+        { role: "user", content: [{ type: "input_text", text: "Before." }] },
+        { type: "configuration_update", reasoning: { effort: "xhigh" } },
+        { role: "user", content: [{ type: "input_text", text: "After." }] },
+      ])
+    }),
+  )
+
+  it.effect("omits reasoning.effort for the model default and sends `medium` for a switch back to it", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model: astra,
+          messages: [
+            Message.user("One."),
+            Message.effort({ effort: "low" }),
+            Message.user("Two."),
+            Message.effort({ previous: "low" }),
+            Message.user("Three."),
+          ],
+        }),
+      )
+
+      expect(prepared.body.reasoning).toBeUndefined()
+      expect(updates(prepared.body)).toEqual([
+        { type: "configuration_update", reasoning: { effort: "low" } },
+        { type: "configuration_update", reasoning: { effort: "medium" } },
+      ])
+    }),
+  )
+
+  it.effect("falls back to a plain top-level effort when history drifted from the current effort", () =>
+    Effect.gen(function* () {
+      const drifted = yield* compileRequest(
+        LLM.request({ model: astra, messages: conversation, providerOptions: { reasoningEffort: "xhigh" } }),
+      )
+      const plain = yield* compileRequest(
+        LLM.request({
+          model: astra,
+          messages: [Message.user("Before."), Message.user("After.")],
+          providerOptions: { reasoningEffort: "xhigh" },
+        }),
+      )
+
+      expect(drifted.body).toEqual(plain.body)
+      expect(drifted.body.reasoning).toEqual({ effort: "xhigh" })
+    }),
+  )
+
+  it.effect("strips markers when automatic context management is enabled", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model: astra,
+          messages: conversation,
+          providerOptions: { reasoningEffort: "low", contextManagement: [{ type: "compaction" }] },
+        }),
+      )
+
+      expect(updates(prepared.body)).toEqual([])
+      expect(prepared.body.reasoning).toEqual({ effort: "low" })
+      expect(prepared.body.context_management).toEqual([{ type: "compaction" }])
+    }),
+  )
+
+  for (const [id, supported] of [
+    ["gpt-6-astra", true],
+    ["openai/gpt-6-astra", true],
+    ["gpt-6-astra-2026-09-01", false],
+    ["gpt-5.6-sol", false],
+  ] as const) {
+    it.effect(`${supported ? "lowers" : "strips"} markers for ${id}`, () =>
+      Effect.gen(function* () {
+        const prepared = yield* compileRequest(
+          LLM.request({ model: openai(id), messages: conversation, providerOptions: { reasoningEffort: "low" } }),
+        )
+
+        expect(updates(prepared.body)).toHaveLength(supported ? 1 : 0)
+        expect(prepared.body.reasoning).toEqual({ effort: supported ? "high" : "low" })
+      }),
+    )
+  }
+
+  it.effect("honors the compatibility override in both directions", () =>
+    Effect.gen(function* () {
+      const enabled = yield* compileRequest(
+        LLM.request({
+          model: openai("gpt-5.5", { supportsEffortUpdates: true }),
+          messages: conversation,
+          providerOptions: { reasoningEffort: "low" },
+        }),
+      )
+      const disabled = yield* compileRequest(
+        LLM.request({
+          model: openai("gpt-6-astra", { supportsEffortUpdates: false }),
+          messages: conversation,
+          providerOptions: { reasoningEffort: "low" },
+        }),
+      )
+
+      expect(updates(enabled.body)).toHaveLength(1)
+      expect(updates(disabled.body)).toHaveLength(0)
+    }),
+  )
+
+  const checkpoint = { type: "compaction", id: "cmp_1", encrypted_content: "opaque" }
+  const compactRequest = LLM.request({
+    model: OpenAI.configure({ apiKey: "fixture" }).responses("gpt-6-astra"),
+    messages: conversation,
+    providerOptions: { reasoningEffort: "low" },
+  })
+
+  testEffect(
+    dynamicResponse(({ text, respond }) =>
+      Effect.sync(() => {
+        const body = JSON.parse(text)
+        expect(body.reasoning).toEqual({ effort: "high" })
+        expect(body.input).toEqual([
+          { role: "user", content: [{ type: "input_text", text: "Before." }] },
+          { type: "configuration_update", reasoning: { effort: "low" } },
+          { role: "user", content: [{ type: "input_text", text: "After." }] },
+          { type: "compaction_trigger" },
+        ])
+        return respond(sseEvents({ type: "response.completed", response: { id: "resp_1", output: [checkpoint] } }), {
+          headers: { "content-type": "text/event-stream" },
+        })
+      }),
+    ),
+  ).effect("keeps configuration updates in the checkpoint body", () =>
+    Effect.gen(function* () {
+      const result = yield* LLMClient.compact(compactRequest, { mechanism: "trigger" })
+      expect(result.checkpoint.encrypted).toBe("opaque")
+    }),
+  )
+
+  testEffect(
+    dynamicResponse(({ request, text, respond }) =>
+      Effect.sync(() => {
+        expect(new URL(request.url).pathname).toEndWith("/responses/compact")
+        expect(JSON.parse(text).input).toEqual([
+          { role: "user", content: [{ type: "input_text", text: "Before." }] },
+          { role: "user", content: [{ type: "input_text", text: "After." }] },
+        ])
+        return respond(JSON.stringify({ object: "response.compaction", output: [checkpoint] }))
+      }),
+    ),
+  ).effect("drops markers from the compaction endpoint body", () =>
+    Effect.gen(function* () {
+      const result = yield* LLMClient.compact(compactRequest, { mechanism: "endpoint" })
+      expect(result.replacement.map((message) => message.content[0]?.type)).toEqual(["compaction"])
+    }),
+  )
+})

packages/ai/test/provider-package.test.ts

@@ -3,6 +3,9 @@ import { model } from "@opencode/ai/providers/openai"
 import { LLM } from "../src/index.js"
 import { Endpoint } from "../src/route/endpoint.js"
 
+const configuration = (provider: string, message: string) =>
+  expect.objectContaining({ _tag: "ProviderConfiguration", provider, message })
+
 describe("provider package entrypoints", () => {
   test("semantic API aliases expose the same contract", async () => {
     const modules = await Promise.all([
@@ -322,7 +325,7 @@ describe("provider package entrypoints", () => {
     const AnthropicCompatible = await import("@opencode/ai/providers/anthropic-compatible")
     expect(() =>
       Reflect.apply(AnthropicCompatible.model, undefined, ["compatible-model", { apiKey: "fixture" }]),
-    ).toThrow("Anthropic-compatible providers require a baseURL")
+    ).toThrow(configuration("anthropic-compatible", "Anthropic-compatible providers require a baseURL"))
   })
 
   test("rejects conflicting Anthropic-compatible auth settings at runtime", async () => {
@@ -337,10 +340,10 @@ describe("provider package entrypoints", () => {
           baseURL: "https://messages.example.test/v1",
         },
       ]),
-    ).toThrow("Anthropic-compatible apiKey cannot be combined with authToken")
+    ).toThrow(configuration("anthropic-compatible", "Anthropic-compatible apiKey cannot be combined with authToken"))
     expect(() =>
       Reflect.apply(Anthropic.model, undefined, ["claude-sonnet-4-6", { apiKey: "fixture", authToken: "token" }]),
-    ).toThrow("Anthropic apiKey cannot be combined with authToken")
+    ).toThrow(configuration("anthropic", "Anthropic apiKey cannot be combined with authToken"))
   })
 
   test("maps legacy OpenAI organization and project settings to headers", () => {
@@ -490,43 +493,45 @@ describe("provider package entrypoints", () => {
         "gemini-3.5-flash",
         { accessToken: "token", apiKey: "fixture", project: "vertex-project" },
       ]),
-    ).toThrow("Google Vertex apiKey cannot be combined with accessToken or auth")
+    ).toThrow(configuration("google-vertex", "Google Vertex apiKey cannot be combined with accessToken or auth"))
     const configured = Reflect.apply(GoogleVertex.configure, undefined, [
       { accessToken: "token", auth: {}, project: "vertex-project" },
     ])
-    expect(() => configured.model("gemini-3.5-flash")).toThrow("Google Vertex accessToken cannot be combined with auth")
+    expect(() => configured.model("gemini-3.5-flash")).toThrow(
+      configuration("google-vertex", "Google Vertex accessToken cannot be combined with auth"),
+    )
     expect(() =>
       Reflect.apply(GoogleVertexMessages.model, undefined, [
         "claude-sonnet-4-6",
         { apiKey: "fixture", project: "vertex-project" },
       ]),
-    ).toThrow("Google Vertex Messages does not support API keys")
+    ).toThrow(configuration("google-vertex", "Google Vertex Messages does not support API keys"))
     expect(() =>
       Reflect.apply(Providers.GoogleVertexMessages.configure, undefined, [
         { apiKey: "fixture", project: "vertex-project" },
       ]),
-    ).toThrow("Google Vertex Messages does not support API keys")
+    ).toThrow(configuration("google-vertex", "Google Vertex Messages does not support API keys"))
     expect(() =>
       Reflect.apply(GoogleVertexChat.model, undefined, [
         "deepseek-ai/deepseek-v3.2-maas",
         { apiKey: "fixture", project: "vertex-project" },
       ]),
-    ).toThrow("Google Vertex Chat does not support API keys")
+    ).toThrow(configuration("google-vertex", "Google Vertex Chat does not support API keys"))
     expect(() =>
       Reflect.apply(Providers.GoogleVertexChat.configure, undefined, [
         { apiKey: "fixture", project: "vertex-project" },
       ]),
-    ).toThrow("Google Vertex Chat does not support API keys")
+    ).toThrow(configuration("google-vertex", "Google Vertex Chat does not support API keys"))
     expect(() =>
       Reflect.apply(GoogleVertexResponses.model, undefined, [
         "xai/grok-4.20-reasoning",
         { apiKey: "fixture", project: "vertex-project" },
       ]),
-    ).toThrow("Google Vertex Responses does not support API keys")
+    ).toThrow(configuration("google-vertex", "Google Vertex Responses does not support API keys"))
     expect(() =>
       Reflect.apply(Providers.GoogleVertexResponses.configure, undefined, [
         { apiKey: "fixture", project: "vertex-project" },
       ]),
-    ).toThrow("Google Vertex Responses does not support API keys")
+    ).toThrow(configuration("google-vertex", "Google Vertex Responses does not support API keys"))
   })
 })

packages/ai/test/provider/alibaba.test.ts

@@ -76,7 +76,13 @@ it.effect("Alibaba owns regional shared and workspace-specific endpoints", () =>
 
 test("Alibaba requires explicit placement and supports complete base URL overrides", () => {
   for (const region of ["eu-central-1", "ap-northeast-1", "future-region"])
-    expect(() => Alibaba.configure({ region })).toThrow("requires workspaceID or baseURL")
+    expect(() => Alibaba.configure({ region })).toThrow(
+      expect.objectContaining({
+        _tag: "ProviderConfiguration",
+        provider: "alibaba",
+        message: `Alibaba region ${region} requires workspaceID or baseURL`,
+      }),
+    )
   for (const config of [
     { baseURL: "https://gateway.example/prefix" },
     { region: "future-region", workspaceID: "ignored", baseURL: "https://gateway.example/prefix" },

packages/ai/test/provider/bedrock-converse.test.ts

@@ -1458,7 +1458,13 @@ describe("Bedrock Converse route", () => {
         expect(headers.get("authorization")).toContain("Credential=AKIACHAINEXAMPLE/")
         expect(headers.get("authorization")).toContain("/ap-southeast-2/bedrock/aws4_request")
       }
-      expect(() => AmazonBedrock.configure({ auth: "sigv4", apiKey: "k" })).toThrow("does not accept apiKey")
+      expect(() => AmazonBedrock.configure({ auth: "sigv4", apiKey: "k" })).toThrow(
+        expect.objectContaining({
+          _tag: "ProviderConfiguration",
+          provider: "amazon-bedrock",
+          message: "Amazon Bedrock SigV4 auth does not accept apiKey",
+        }),
+      )
     }).pipe(
       withProcessEnv({
         ...noAmbientAWS,

packages/ai/test/provider/google-vertex.test.ts

@@ -378,7 +378,11 @@ describe("Google Vertex providers", () => {
 
   test("rejects tuned Gemini models in express mode", () => {
     expect(() => GoogleVertex.configure({ apiKey: "fixture" }).model("endpoints/1234567890")).toThrow(
-      "Google Vertex tuned models do not support Express Mode API keys",
+      expect.objectContaining({
+        _tag: "ProviderConfiguration",
+        provider: "google-vertex",
+        message: "Google Vertex tuned models do not support Express Mode API keys",
+      }),
     )
   })
 })

packages/ai/test/provider/open-responses-errors.test.ts

@@ -0,0 +1,78 @@
+import { expect } from "bun:test"
+import { Effect, Schema } from "effect"
+import { LLM, LLMClient } from "../../src/index.js"
+import { OpenResponses } from "../../src/protocols/open-responses.js"
+import { Meta } from "../../src/providers/index.js"
+import { configure } from "../../src/providers/openai-compatible-responses.js"
+import { it } from "../lib/effect.js"
+import { fixedResponse } from "../lib/http.js"
+import { sseEvents } from "../lib/sse.js"
+
+const decodeEvent = Schema.decodeUnknownEffect(OpenResponses.protocol.stream.event)
+
+it.effect("normalizes flat errors in shared SSE and WebSocket decoding", () =>
+  Effect.gen(function* () {
+    const frame = {
+      type: "error",
+      sequence_number: 4,
+      code: "server_shutting_down",
+      message: "Server is shutting down. Please retry your request.",
+      param: null,
+    }
+    for (const decode of [decodeEvent, OpenResponses.decodeChannelEvent]) {
+      const event = yield* decode(JSON.stringify(frame))
+      expect(event).toEqual({
+        type: "error",
+        sequence_number: 4,
+        error: { code: frame.code, message: frame.message, param: null },
+      })
+
+      for (const unchanged of [
+        event,
+        { type: "error" },
+        {
+          type: "response.failed",
+          response: { id: "resp_failed", error: { code: "server_error", message: "Internal server error" } },
+        },
+        { type: "response.output_text.delta", item_id: "msg_text", delta: "Hello" },
+      ]) {
+        expect(yield* decode(JSON.stringify(unchanged))).toEqual(unchanged)
+      }
+    }
+  }),
+)
+
+it.effect("continues to normalize untyped xAI WebSocket errors", () =>
+  Effect.gen(function* () {
+    const frame = { error: { type: "api_error", message: "gRPC error: Response with id=resp_missing not found" } }
+    expect(yield* OpenResponses.decodeChannelEvent(JSON.stringify(frame))).toEqual({ ...frame, type: "error" })
+  }),
+)
+
+it.effect("retains classification and original error bodies through Meta and generic Responses routes", () =>
+  Effect.gen(function* () {
+    const raw = `{
+  "type": "error",
+  "sequence_number": 4,
+  "code": "server_shutting_down",
+  "message": "Server is shutting down. Please retry your request.",
+  "param": null,
+  "diagnostic": "retain-original-frame"
+}`
+    for (const model of [
+      Meta.configure({ apiKey: "fixture" }).responses("muse-spark-1.3"),
+      configure({ apiKey: "fixture", provider: "gateway", baseURL: "https://responses.example.test/v1" }).model(
+        "example-model",
+      ),
+    ]) {
+      const error = yield* LLMClient.generate(LLM.request({ model, prompt: "Hello" })).pipe(
+        Effect.provide(fixedResponse(sseEvents(raw.replaceAll("\n", "\ndata: ")))),
+        Effect.flip,
+      )
+      expect(error.reason._tag).toBe("ProviderInternal")
+      expect(error.message).toBe("server_shutting_down: Server is shutting down. Please retry your request.")
+      expect(error.reason.body).toBe(raw)
+      expect(error.reason.http?.status).toBe(200)
+    }
+  }),
+)

packages/ai/test/provider/openai-responses.test.ts

@@ -90,7 +90,11 @@ const classifyingChannelDriver = (message: string): WebSocketChannelDriver => {
   }
 }
 
-const continuationDriver = (request: Readonly<Record<string, unknown>>, base = baseChannelDriver) => {
+const continuationDriver = (
+  request: Readonly<Record<string, unknown>>,
+  base = baseChannelDriver,
+  continuation?: OpenResponsesContinuation.Shape,
+) => {
   const message = ProviderShared.encodeJson(request)
   return OpenResponsesContinuation.driver({
     id: "openai-responses",
@@ -98,6 +102,7 @@ const continuationDriver = (request: Readonly<Record<string, unknown>>, base = b
     request,
     message,
     base: base(message),
+    continuation,
   })
 }
 
@@ -921,6 +926,58 @@ describe("OpenAI Responses route", () => {
         type: "provider-failure",
         error: { reason: { _tag: "InvalidRequest", classification: "context-overflow" } },
       })
+
+      // A retryable failure stays one: the runner retries it, and the transport has already dropped the
+      // checkpoint, so that retry is a full send. xAI reports every rejection this way.
+      const internal = ProviderShared.encodeJson({
+        type: "error",
+        error: { type: "api_error", message: "gRPC error: Response with id=resp_1 not found" },
+      })
+      expect(yield* second.observe(yield* second.create(saved), internal)).toMatchObject({
+        type: "provider-failure",
+        error: { reason: { _tag: "ProviderInternal" } },
+      })
+    }),
+  )
+
+  it.effect("shapes the incremental send with the route continuation", () =>
+    Effect.gen(function* () {
+      const firstRequest = {
+        type: "response.create",
+        model: "grok-4.6",
+        store: true,
+        instructions: "You are terse.",
+        input: [{ role: "user", content: [{ type: "input_text", text: "First" }] }],
+      }
+      const secondRequest = {
+        ...firstRequest,
+        input: [...firstRequest.input, { role: "user", content: [{ type: "input_text", text: "Second" }] }],
+      }
+      const saved = checkpoint(
+        yield* continuationDriver(firstRequest).observe(
+          yield* continuationDriver(firstRequest).create(undefined),
+          ProviderShared.encodeJson({ type: "response.completed", response: { id: "resp_1" } }),
+        ),
+      )
+
+      const trimmed = yield* continuationDriver(
+        secondRequest,
+        baseChannelDriver,
+        ({ instructions: _, ...rest }) => rest,
+      ).create(saved)
+      expect(trimmed.mode).toBe("incremental")
+      expect(JSON.parse(trimmed.message)).toEqual({
+        type: "response.create",
+        model: "grok-4.6",
+        store: true,
+        previous_response_id: "resp_1",
+        input: [{ role: "user", content: [{ type: "input_text", text: "Second" }] }],
+      })
+
+      // Declining the continuation sends the step in full and never sends a previous_response_id.
+      const declined = yield* continuationDriver(secondRequest, baseChannelDriver, () => undefined).create(saved)
+      expect(declined.mode).toBe("full")
+      expect(JSON.parse(declined.message)).toEqual(secondRequest)
     }),
   )
 

packages/ai/test/provider/xai-responses.test.ts

@@ -1,11 +1,18 @@
 import { describe, expect } from "bun:test"
-import { Effect } from "effect"
+import { Effect, Layer, Stream } from "effect"
 import { LLM, LLMEvent, Message } from "../../src/index.js"
 import { XAI } from "../../src/providers.js"
 import { OpenResponses } from "../../src/protocols/open-responses.js"
 import { OpenAIResponses } from "../../src/protocols/openai-responses.js"
+import * as ProviderShared from "../../src/protocols/shared.js"
 import { XAIResponses } from "../../src/protocols/xai-responses.js"
-import { LLMClient } from "../../src/route.js"
+import {
+  LLMClient,
+  RequestExecutor,
+  WebSocketTransport,
+  type ChannelCheckpoint,
+  type WebSocketChannelDriver,
+} from "../../src/route.js"
 import { compileRequest } from "../../src/route/client.js"
 import { it } from "../lib/effect.js"
 import { fixedResponse } from "../lib/http.js"
@@ -13,6 +20,35 @@ import { sseEvents } from "../lib/sse.js"
 
 const model = XAI.configure({ apiKey: "test", baseURL: "https://api.x.ai/v1" }).responses("grok-4.6")
 
+/** Runs a request through the WebSocket transport and hands back its channel driver; the HTTP fallback answers. */
+const channelDriver = (request: ReturnType<typeof LLM.request>) =>
+  Effect.gen(function* () {
+    let driver: WebSocketChannelDriver | undefined
+    yield* LLMClient.generate(request, {
+      webSocket: {
+        execute: (exchange) =>
+          Effect.sync(() => {
+            driver = exchange.driver
+            return { frames: exchange.fallback(), complete: Effect.void }
+          }),
+      },
+    }).pipe(Effect.provide(fixedResponse(sseEvents({ type: "response.completed", response: { id: "http" } }))))
+    if (!driver) throw new Error("Expected a WebSocket channel driver")
+    return driver
+  })
+
+const completed = (driver: WebSocketChannelDriver, id: string) =>
+  Effect.gen(function* () {
+    const create = yield* driver.create(undefined)
+    yield* driver.observe(create, ProviderShared.encodeJson({ type: "response.created", response: { id } }))
+    const observation = yield* driver.observe(
+      create,
+      ProviderShared.encodeJson({ type: "response.completed", response: { id } }),
+    )
+    if (observation.type !== "completed" || !observation.checkpoint) throw new Error("Expected a checkpoint")
+    return observation.checkpoint
+  })
+
 describe("xAI Responses route", () => {
   it.effect("composes the Open Responses baseline with xAI extensions", () =>
     Effect.gen(function* () {
@@ -162,6 +198,78 @@ describe("xAI Responses route", () => {
     }),
   )
 
+  it.effect("classifies xAI's untyped WebSocket error envelope", () =>
+    Effect.gen(function* () {
+      // xAI answers a rejected response.create with an error envelope that carries no event type.
+      const envelope = ProviderShared.encodeJson({
+        error: {
+          message:
+            'Request validation error: {"code":"400","error":"Argument not supported: instructions and previous_response_id together"}',
+          type: "api_error",
+        },
+      })
+      const webSocket = WebSocketTransport.makeDirect({
+        open: () =>
+          Effect.succeed({ sendText: () => Effect.void, messages: Stream.make(envelope), close: Effect.void }),
+      })
+      const error = yield* LLMClient.generate(LLM.request({ model, prompt: "Hello" }), { webSocket }).pipe(
+        Effect.provide(
+          LLMClient.layer.pipe(
+            Layer.provide(
+              Layer.succeed(
+                RequestExecutor.Service,
+                RequestExecutor.Service.of({ execute: () => Effect.die("unexpected HTTP request") }),
+              ),
+            ),
+          ),
+        ),
+        Effect.flip,
+      )
+
+      expect(error.reason._tag).toBe("ProviderInternal")
+      expect(error.message).toContain("Argument not supported: instructions and previous_response_id together")
+      expect(error.reason.body).toBe(envelope)
+    }),
+  )
+
+  it.effect("continues stored responses without instructions and sends unstored steps in full", () =>
+    Effect.gen(function* () {
+      const step = (store: boolean, ...prompts: string[]) =>
+        LLM.request({
+          model,
+          system: "You are terse.",
+          messages: prompts.map((prompt) => Message.user(prompt)),
+          providerOptions: { store },
+        })
+      const send = (store: boolean, checkpoint: ChannelCheckpoint) =>
+        channelDriver(step(store, "First", "Second")).pipe(Effect.flatMap((driver) => driver.create(checkpoint)))
+
+      const stored = yield* send(true, yield* completed(yield* channelDriver(step(true, "First")), "resp_1"))
+      expect(stored.mode).toBe("incremental")
+      expect(JSON.parse(stored.message)).toEqual({
+        type: "response.create",
+        model: "grok-4.6",
+        store: true,
+        include: ["reasoning.encrypted_content"],
+        previous_response_id: "resp_1",
+        input: [{ role: "user", content: [{ type: "input_text", text: "Second" }] }],
+      })
+
+      // The connection cache only serves stored responses, so the default store: false never chains.
+      const unstored = yield* send(false, yield* completed(yield* channelDriver(step(false, "First")), "resp_1"))
+      expect(unstored.mode).toBe("full")
+      expect(JSON.parse(unstored.message)).toMatchObject({
+        instructions: "You are terse.",
+        store: false,
+        input: [
+          { role: "user", content: [{ type: "input_text", text: "First" }] },
+          { role: "user", content: [{ type: "input_text", text: "Second" }] },
+        ],
+      })
+      expect(JSON.parse(unstored.message).previous_response_id).toBeUndefined()
+    }),
+  )
+
   it.effect("parses xAI hosted tool items", () =>
     Effect.gen(function* () {
       const item = { type: "x_search_call", id: "x_search_1", status: "completed", action: { query: "news" } }

packages/app/component-tests/ssh-reconnect.spec.ts

@@ -19,11 +19,13 @@ story("cancelling a version mismatch permits reconnecting again", async ({ mount
   const component = await mount("app-dialog-ssh--incompatible-session")
   await component.getByRole("button", { name: "Reconnect", exact: true }).click()
   const dialog = page.getByRole("dialog")
-  await expect(dialog.getByRole("alert")).toBeVisible()
+  await expect(dialog.getByRole("status")).toContainText("Server update required")
+  await expect(dialog.getByRole("textbox")).toHaveCount(0)
   await dialog.getByRole("button", { name: "Cancel", exact: true }).click()
   await expect(dialog).toHaveCount(0)
   await component.getByRole("button", { name: "Reconnect", exact: true }).click()
-  await expect(dialog.getByRole("alert")).toBeVisible()
+  await expect(dialog.getByRole("status")).toContainText("Server update required")
+  await expect(dialog.getByRole("textbox")).toHaveCount(0)
   await dialog.getByRole("button", { name: "Cancel", exact: true }).click()
   await expect(dialog).toHaveCount(0)
 })
@@ -43,6 +45,17 @@ story("adding a server keeps all SSH challenges in the original connection dialo
   await expect(dialog).toHaveCount(0)
 })
 
+story("adding an incompatible server advances to a dedicated update step", async ({ mount, page }) => {
+  await mount("app-dialog-ssh--incompatible-host")
+  const dialog = page.getByRole("dialog")
+  await dialog.getByRole("textbox", { name: "Host or SSH command" }).fill("ssh devbox")
+  await dialog.getByRole("button", { name: "Add server", exact: true }).click()
+  await expect(dialog.getByRole("status")).toContainText("Server update required")
+  await expect(dialog.getByRole("textbox")).toHaveCount(0)
+  await expect(dialog.getByRole("alert")).toHaveCount(0)
+  await expect(dialog.getByRole("button", { name: "Update and reconnect", exact: true })).toBeVisible()
+})
+
 story("updating an incompatible connection continues authentication in the same dialog", async ({ mount, page }) => {
   const component = await mount("app-dialog-ssh--incompatible-session")
   await component.getByRole("button", { name: "Reconnect", exact: true }).click()

packages/app/e2e/regression/session-timeline-reducer-projection.spec.ts

@@ -115,7 +115,7 @@ test("combines follow-up patches into one three-file stack inside Used", async (
   })
   const group = page.locator('[data-component="collapsed-tool-group"]')
   await group.getByRole("button", { name: "Used 2 Shell, Patch", exact: true }).click()
-  await expect(group.getByText("2 files", { exact: true })).toBeVisible()
+  await expect(group.locator('[data-slot="apply-patch-filename"]')).toHaveText(["a.ts", "b.ts"])
   await timeline.send(
     partUpdated(
       toolPart(
@@ -134,7 +134,6 @@ test("combines follow-up patches into one three-file stack inside Used", async (
     "true",
   )
   await expect(group.locator('[data-component="apply-patch-tool"]')).toHaveCount(1)
-  await expect(group.getByText("3 files", { exact: true })).toBeVisible()
   await expect(group.locator('[data-slot="apply-patch-filename"]')).toHaveText(["a.ts", "b.ts", "c.ts"])
 })
 

packages/app/src/composer/submit.ts

@@ -126,15 +126,9 @@ export function createComposerSubmit(input: ComposerSubmitInput) {
 
       if (command) {
         clearSubmission(input, submission)
-        // Commands always steer: the server applies a command's configured
-        // agent and model immediately at admission, so queueing one would
-        // reconfigure the turn it is supposed to wait behind.
-        void sendCommand(
-          session,
-          { ...value, delivery: "steer" },
-          command,
-          input.adapter.controls().model.selection.trackSessionCommit,
-        ).catch((error) => failSubmission(input, session, "command", error, restore, value.id))
+        void sendCommand(session, value, command, input.adapter.controls().model.selection.trackSessionCommit).catch(
+          (error) => failSubmission(input, session, "command", error, restore, value.id),
+        )
         return
       }
     } finally {
@@ -326,7 +320,8 @@ async function sendCommand(
   track?: ModelSelection["trackSessionCommit"],
 ) {
   const request = await buildSubmissionRequest(session, value)
-  await applySelection(session, value.selection, track)
+  // Like queued prompts, queued commands must not apply the composer's selection to active work.
+  if (value.delivery === "steer") await applySelection(session, value.selection, track)
   await session.api.command({
     sessionID: session.id,
     command: command.command,

packages/app/src/runtime/platform/web.ts

@@ -54,8 +54,12 @@ export function createWebPlatform(version: string) {
 
 function getCurrentServerUrl() {
   if (import.meta.env.VITE_OPENCODE_SERVER_MODE === "none") return undefined
-  if (import.meta.env.DEV)
-    return `http://${import.meta.env.VITE_OPENCODE_SERVER_HOST ?? "localhost"}:${import.meta.env.VITE_OPENCODE_SERVER_PORT ?? "4096"}`
+  if (import.meta.env.DEV) {
+    const loopback =
+      location.hostname === "localhost" || location.hostname === "[::1]" || location.hostname.startsWith("127.")
+    const host = import.meta.env.VITE_OPENCODE_SERVER_HOST ?? (loopback ? location.hostname : "localhost")
+    return `http://${host}:${import.meta.env.VITE_OPENCODE_SERVER_PORT ?? "4096"}`
+  }
   return location.origin
 }
 

packages/app/src/runtime/server/runtime.tsx

@@ -10,6 +10,7 @@ import { createData } from "@opencode/client/solid"
 import type { ServerScope } from "@/runtime/server/scope"
 import { createPermissionAutoApprover } from "@/session/requests/auto-approve"
 import { createServerNotificationState } from "@/shell/notifications/notification"
+import { createNotificationCoordinator } from "@/shell/notifications/coordinator"
 import { Persist, persisted } from "@/runtime/persistence/storage"
 import { createDesktopData } from "./data"
 import { ModelState } from "./persistence"
@@ -33,6 +34,7 @@ export const { use: useGlobal, provider: GlobalProvider } = createSimpleContext(
       },
     })
     const models = createGlobalModels()
+    const notificationCoordinator = createNotificationCoordinator()
 
     const settingsServer = createMemo(() => {
       const list = server.list
@@ -57,7 +59,7 @@ export const { use: useGlobal, provider: GlobalProvider } = createSimpleContext(
       if (existing) return existing
       const serverCtx = createRoot((dispose) => {
         serverCtxDisposers.set(key, dispose)
-        return createServerController(conn, server.scope(key), server.projects.forServer(key))
+        return createServerController(conn, server.scope(key), server.projects.forServer(key), notificationCoordinator)
       }, owner)
       serverCtxs.set(key, serverCtx)
       return serverCtx
@@ -131,6 +133,7 @@ function createServerController(
   conn: ServerConnection.Any,
   scope: ServerScope,
   projects: ReturnType<typeof createServerProjects>,
+  notificationCoordinator: ReturnType<typeof createNotificationCoordinator>,
 ) {
   const language = useLanguage()
   const settings = useSettings()
@@ -159,7 +162,7 @@ function createServerController(
   })
   const sync = createServerSyncContext(sdk, data)
   createPermissionAutoApprover({ sdk, data })
-  const notification = createServerNotificationState({ sdk, data, key: connKey })
+  const notification = createServerNotificationState({ sdk, data, key: connKey, coordinator: notificationCoordinator })
 
   function enrich(project: { worktree: string; expanded: boolean }) {
     const [childStore] = sync.child(project.worktree, { bootstrap: false })

packages/app/src/servers/ssh/dialog.stories.tsx

@@ -278,6 +278,7 @@ function Open(props: { initial?: string }) {
 export default { title: "App/Dialogs/SSH", id: "app-dialog-ssh" }
 export const AuthenticationRequired = { render: () => <Fixture initial="required" /> }
 export const SettingsReconnect = { render: () => <Fixture initial="required" settings connectionDelay={200} /> }
+export const IncompatibleHost = { render: () => <Fixture incompatible /> }
 export const IncompatibleSession = { render: () => <Fixture initial="required" session incompatible /> }
 export const InactiveSession = { render: () => <Fixture initial="required" session connectionDelay={3000} /> }
 export const KeyReconnect = { render: () => <Fixture initial="required" session keyOnly connectionDelay={3000} /> }

packages/app/src/servers/ssh/dialog.tsx

@@ -120,7 +120,13 @@ export function DialogSsh(props: {
       <Divider />
       <DialogBody class="flex w-full min-w-0 flex-1 flex-col px-4 pt-4 pb-2">
         <div class="flex w-full min-w-0 flex-col gap-6">
-          <Show when={!props.promptOnly && (!state.prompted || (!!error() && !prompt()))}>
+          <Show
+            when={
+              !props.promptOnly &&
+              item()?.stage !== "incompatible" &&
+              (!state.prompted || (!!error() && !prompt()))
+            }
+          >
             <div class="flex w-full min-w-0 flex-col gap-2">
               <label class="settings-server-dialog-label" for="ssh-target">
                 {language.t("ssh.target")}
@@ -160,6 +166,12 @@ export function DialogSsh(props: {
               />
             </div>
           </Show>
+          <Show when={item()?.stage === "incompatible"}>
+            <div class="flex w-full min-w-0 flex-col gap-2" role="status" aria-live="polite">
+              <span class="text-14-medium text-v2-text-text-base">{language.t("ssh.stage.incompatible")}</span>
+              <span class="text-13-regular text-v2-text-text-muted">{language.t("ssh.error.version")}</span>
+            </div>
+          </Show>
           <Show when={prompt()} keyed>
             {(prompt) => (
               <div class="flex w-full min-w-0 flex-col gap-2">
@@ -195,7 +207,7 @@ export function DialogSsh(props: {
               </div>
             )}
           </Show>
-          <Show when={error()}>
+          <Show when={item()?.stage !== "incompatible" && error()}>
             {(error) => (
               <span class="settings-server-dialog-error !leading-[var(--line-height-compact)]" role="alert">
                 {error()}

packages/app/src/session/files/session-file-browser-tab.tsx

@@ -1,6 +1,6 @@
 import { createMemo, createUniqueId, Show } from "solid-js"
 import { createStore } from "solid-js/store"
-import { createQuery } from "@tanstack/solid-query"
+import { createQuery, keepPreviousData } from "@tanstack/solid-query"
 import { Icon } from "@opencode/ui/icon"
 import { SessionFilePanelV2, SessionFilePanelV2Empty } from "@opencode/session-ui/v2/session-file-panel-v2"
 import { SessionReviewV2Sidebar } from "@opencode/session-ui/v2/session-review-v2"
@@ -56,6 +56,7 @@ export function SessionFileBrowserTab(props: {
       queryKey: [serverSDK.scope, "session-open-file", workspaceKey(), value] as const,
       enabled: serverSDK.connection.status() === "connected" && value.length > 0,
       queryFn: ({ signal }) => file.searchFiles(value, { limit: 200, signal }),
+      placeholderData: keepPreviousData,
     }
   })
   const files = createMemo(() => {

packages/app/src/shell/notifications/coordinator.ts

@@ -0,0 +1,93 @@
+import { onCleanup } from "solid-js"
+
+const FOCUS_LOCK = "opencode:notification-focus"
+const MAX_CLAIMED = 500
+
+export function createNotificationCoordinator() {
+  const locks = typeof navigator === "undefined" ? undefined : navigator.locks
+  const claimed = new Set<string>()
+  const focus = { pending: false, release: undefined as (() => void) | undefined }
+
+  const updateFocus = () => {
+    if (typeof document === "undefined" || !document.hasFocus()) {
+      focus.release?.()
+      return
+    }
+    if (!locks || focus.pending || focus.release) return
+
+    focus.pending = true
+    void locks
+      .request(FOCUS_LOCK, { mode: "shared" }, async () => {
+        focus.pending = false
+        if (!document.hasFocus()) return
+        await new Promise<void>((resolve) => {
+          focus.release = resolve
+        })
+        focus.release = undefined
+      })
+      .catch(() => {
+        focus.pending = false
+      })
+  }
+
+  if (typeof window !== "undefined") {
+    window.addEventListener("focus", updateFocus)
+    window.addEventListener("blur", updateFocus)
+    document.addEventListener("visibilitychange", updateFocus)
+    updateFocus()
+    onCleanup(() => {
+      window.removeEventListener("focus", updateFocus)
+      window.removeEventListener("blur", updateFocus)
+      document.removeEventListener("visibilitychange", updateFocus)
+      focus.release?.()
+    })
+  }
+
+  const once = async (kind: "sound" | "system", eventID: string, run: () => Promise<unknown> | void) => {
+    const key = `${kind}:${eventID}`
+    const execute = async () => {
+      if (!claim(kind, key, claimed)) return
+      await run()
+    }
+    if (!locks) return execute()
+    await locks.request(`opencode:notification:${key}`, execute)
+  }
+
+  return {
+    sound(eventID: string, run: () => Promise<unknown> | void) {
+      return once("sound", eventID, run)
+    },
+    system(eventID: string, run: () => Promise<unknown> | void) {
+      return once("system", eventID, async () => {
+        if (typeof document !== "undefined" && document.hasFocus()) return
+        if (!locks) return run()
+        await locks.request(FOCUS_LOCK, { mode: "exclusive", ifAvailable: true }, async (lock) => {
+          if (!lock) return
+          await run()
+        })
+      })
+    },
+  }
+}
+
+function claim(kind: "sound" | "system", eventID: string, claimed: Set<string>) {
+  if (claimed.has(eventID)) return false
+
+  if (typeof localStorage !== "undefined") {
+    try {
+      const storageKey = `opencode:notification-${kind}`
+      const value: unknown = JSON.parse(localStorage.getItem(storageKey) ?? "[]")
+      const events = Array.isArray(value) ? value.filter((item): item is string => typeof item === "string") : []
+      if (events.includes(eventID)) {
+        claimed.add(eventID)
+        return false
+      }
+      localStorage.setItem(storageKey, JSON.stringify([...events, eventID].slice(-MAX_CLAIMED)))
+    } catch {
+      // The in-memory claim still prevents duplicates in this renderer when storage is unavailable.
+    }
+  }
+
+  claimed.add(eventID)
+  return true
+}

packages/app/src/shell/notifications/notification.tsx

@@ -11,7 +11,8 @@ import { useSettings } from "@/settings/model"
 import { decode64 } from "@/runtime/persistence/base64"
 import { Persist, persisted } from "@/runtime/persistence/storage"
 import { Persistence } from "@/runtime/persistence/schema"
-import { playSoundByIdOnce } from "@/shell/notifications/sound"
+import { playSoundById } from "@/shell/notifications/sound"
+import type { createNotificationCoordinator } from "@/shell/notifications/coordinator"
 import { useGlobal } from "@/runtime/server/runtime"
 import { ServerConnection, useServers } from "@/runtime/server/registry"
 import { sessionIDHasOpenTab, useTabs } from "@/shell/tabs/tabs"
@@ -114,7 +115,12 @@ function buildNotificationIndex(list: Notification[]) {
   return index
 }
 
-export function createServerNotificationState(input: { sdk: ServerSDK; data: Data; key: ServerConnection.Key }) {
+export function createServerNotificationState(input: {
+  sdk: ServerSDK
+  data: Data
+  key: ServerConnection.Key
+  coordinator: ReturnType<typeof createNotificationCoordinator>
+}) {
   const platform = usePlatform()
   const settings = useSettings()
   const language = useLanguage()
@@ -223,7 +229,7 @@ export function createServerNotificationState(input: { sdk: ServerSDK; data: Dat
       if (session.parentID) return
 
       if (sessionIDHasOpenTab(tabs.store, input.key, sessionID) && settings.sounds.agentEnabled()) {
-        void playSoundByIdOnce(settings.sounds.agent(), `${input.key}\0${eventID}`)
+        void input.coordinator.sound(`${input.key}\0${eventID}`, () => playSoundById(settings.sounds.agent()))
       }
 
       append({
@@ -235,8 +241,10 @@ export function createServerNotificationState(input: { sdk: ServerSDK; data: Dat
       })
 
       if (settings.notifications.agent()) {
-        void platform.notify(language.t("notification.session.responseReady.title"), session.title ?? sessionID, () =>
-          openNotificationSession(tabs, input.key, sessionID),
+        void input.coordinator.system(`${input.key}\0${eventID}`, () =>
+          platform.notify(language.t("notification.session.responseReady.title"), session.title ?? sessionID, () =>
+            openNotificationSession(tabs, input.key, sessionID),
+          ),
         )
       }
     })
@@ -248,7 +256,7 @@ export function createServerNotificationState(input: { sdk: ServerSDK; data: Dat
       if (session?.parentID) return
 
       if (sessionIDHasOpenTab(tabs.store, input.key, sessionID) && settings.sounds.errorsEnabled()) {
-        void playSoundByIdOnce(settings.sounds.errors(), `${input.key}\0${eventID}`)
+        void input.coordinator.sound(`${input.key}\0${eventID}`, () => playSoundById(settings.sounds.errors()))
       }
 
       append({
@@ -263,8 +271,10 @@ export function createServerNotificationState(input: { sdk: ServerSDK; data: Dat
         session?.title ??
         (typeof error === "string" ? error : language.t("notification.session.error.fallbackDescription"))
       if (settings.notifications.errors()) {
-        void platform.notify(language.t("notification.session.error.title"), description, () =>
-          openNotificationSession(tabs, input.key, sessionID),
+        void input.coordinator.system(`${input.key}\0${eventID}`, () =>
+          platform.notify(language.t("notification.session.error.title"), description, () =>
+            openNotificationSession(tabs, input.key, sessionID),
+          ),
         )
       }
     })

packages/app/src/shell/notifications/sound.ts

@@ -74,9 +74,6 @@ function getLoads() {
 }
 
 const cache = new Map<SoundID, Promise<string | undefined>>()
-const claimed = new Set<string>()
-const CLAIMED_STORAGE_KEY = "opencode:notification-sounds"
-const MAX_CLAIMED = 500
 
 export function soundSrc(id: string | undefined) {
   const loads = getLoads()
@@ -103,34 +100,3 @@ export function playSound(src: string | undefined) {
 export function playSoundById(id: string | undefined) {
   return soundSrc(id).then((src) => playSound(src))
 }
-
-export async function playSoundByIdOnce(id: string | undefined, eventID: string) {
-  const play = async () => {
-    if (!claim(eventID)) return
-    await playSoundById(id)
-  }
-
-  if (typeof navigator === "undefined" || !navigator.locks) return play()
-  await navigator.locks.request(`${CLAIMED_STORAGE_KEY}:${eventID}`, play)
-}
-
-function claim(eventID: string) {
-  if (claimed.has(eventID)) return false
-
-  if (typeof localStorage !== "undefined") {
-    try {
-      const value: unknown = JSON.parse(localStorage.getItem(CLAIMED_STORAGE_KEY) ?? "[]")
-      const events = Array.isArray(value) ? value.filter((item): item is string => typeof item === "string") : []
-      if (events.includes(eventID)) {
-        claimed.add(eventID)
-        return false
-      }
-      localStorage.setItem(CLAIMED_STORAGE_KEY, JSON.stringify([...events, eventID].slice(-MAX_CLAIMED)))
-    } catch {
-      // The in-memory claim still prevents duplicates in this renderer when storage is unavailable.
-    }
-  }
-
-  claimed.add(eventID)
-  return true
-}

packages/cli/src/acp/config-option.ts

@@ -76,7 +76,10 @@ export function buildEffortSelectOption(input: {
     category: "thought_level",
     type: "select",
     currentValue: selectVariant(input.currentVariant, input.variants),
-    options: input.variants.map((variant) => ({ value: variant, name: formatVariantName(variant) })),
+    options: [...new Set([...input.variants, DEFAULT_VARIANT_VALUE])].map((variant) => ({
+      value: variant,
+      name: formatVariantName(variant),
+    })),
   }
 }
 
@@ -125,6 +128,7 @@ export function formatVariantName(variant: string) {
 }
 
 function selectVariant(variant: string | undefined, variants: readonly string[]) {
+  if (!variant || variant === DEFAULT_VARIANT_VALUE) return DEFAULT_VARIANT_VALUE
   if (variant && variants.includes(variant)) return variant
   if (variants.includes(DEFAULT_VARIANT_VALUE)) return DEFAULT_VARIANT_VALUE
   return variants[0] ?? DEFAULT_VARIANT_VALUE

packages/cli/src/acp/event.ts

@@ -201,7 +201,7 @@ export async function streamTurn(input: {
         if (!child) assistantMessageID = event.data.assistantMessageID
         await send({
           sessionUpdate: "agent_thought_chunk",
-          messageId: event.data.assistantMessageID,
+          messageId: `${event.data.assistantMessageID}:reasoning:${event.data.ordinal}`,
           content: { type: "text", text: event.data.delta },
         })
         continue
@@ -455,6 +455,8 @@ async function replayMessage(
     return
   }
   if (message.type !== "assistant") return
+  // Live reasoning ordinals count only reasoning parts, not the mixed content array.
+  let reasoningOrdinal = 0
   for (const part of message.content) {
     if (part.type === "text") {
       await connection.sessionUpdate({
@@ -472,7 +474,7 @@ async function replayMessage(
         sessionId: sessionID,
         update: {
           sessionUpdate: "agent_thought_chunk",
-          messageId: message.id,
+          messageId: `${message.id}:reasoning:${reasoningOrdinal++}`,
           content: { type: "text", text: part.text },
         },
       })

packages/cli/src/acp/service.ts

@@ -41,7 +41,12 @@ import type {
 } from "@agentclientprotocol/sdk"
 import { OPENCODE_VERSION } from "../version"
 import { SessionMessage } from "@opencode/schema/session-message"
-import { buildConfigOptions, parseModelSelection, type ConfigOptionProvider } from "./config-option"
+import {
+  buildConfigOptions,
+  DEFAULT_VARIANT_VALUE,
+  parseModelSelection,
+  type ConfigOptionProvider,
+} from "./config-option"
 import { promptContentToParts } from "./content"
 import {
   ChildSessionUpdateMethod,
@@ -275,7 +280,7 @@ export function make(input: { readonly client: OpenCodeClient; readonly connecti
       if (typeof params.value !== "string") throw new ACPError.InvalidConfigOptionError({ configId: params.configId })
       switch (params.configId) {
         case "model": {
-          const selected = requireModel(state.catalog, params.value)
+          const selected = requireModel(state.catalog, params.value, state.model)
           state.model = selected
           await input.client.session.switchModel({ sessionID: state.id, model: selected })
           break
@@ -284,7 +289,10 @@ export function make(input: { readonly client: OpenCodeClient; readonly connecti
           const model = state.catalog.models.find(
             (item) => item.providerID === state.model.providerID && item.id === state.model.id,
           )
-          if (!model?.variants.some((variant) => variant.id === params.value))
+          if (
+            !model ||
+            (params.value !== DEFAULT_VARIANT_VALUE && !model.variants.some((variant) => variant.id === params.value))
+          )
             throw new ACPError.InvalidEffortError({ effort: params.value })
           state.model = { ...state.model, variant: params.value }
           await input.client.session.switchModel({ sessionID: state.id, model: state.model })
@@ -453,7 +461,7 @@ function providers(models: readonly ModelInfo[]): ConfigOptionProvider[] {
     }))
 }
 
-function requireModel(catalog: Catalog, modelID: string): ModelRef {
+function requireModel(catalog: Catalog, modelID: string, current: ModelRef): ModelRef {
   const selected = parseModelSelection(modelID, catalog.providers)
   const model = catalog.models.find(
     (item) => item.providerID === selected.model.providerID && item.id === selected.model.modelID,
@@ -461,7 +469,14 @@ function requireModel(catalog: Catalog, modelID: string): ModelRef {
   if (!model) throw new ACPError.InvalidModelError({ providerId: selected.model.providerID, modelId: modelID })
   if (selected.variant && !model.variants.some((variant) => variant.id === selected.variant))
     throw new ACPError.InvalidEffortError({ effort: selected.variant })
-  return { providerID: model.providerID, id: model.id, variant: selected.variant }
+  const variant =
+    selected.variant ??
+    (current.providerID === model.providerID &&
+    current.id === model.id &&
+    (current.variant === DEFAULT_VARIANT_VALUE || model.variants.some((variant) => variant.id === current.variant))
+      ? current.variant
+      : undefined)
+  return { providerID: model.providerID, id: model.id, variant }
 }
 
 async function selectMode(client: OpenCodeClient, state: Attached, modeID: string) {

packages/cli/src/commands/handlers/session/list.ts

@@ -47,7 +47,7 @@ const handler = Effect.fn("cli.session.list")(function* (
           null,
           2,
         )
-      : formatTable(page.data)) + EOL
+      : formatList(page.data)) + EOL
   const write = Effect.tryPromise(
     () =>
       new Promise<void>((resolve, reject) => {
@@ -96,18 +96,14 @@ export default Runtime.handler(Commands.commands.session.commands.list, (input)
   ),
 )
 
-function formatTable(sessions: ReadonlyArray<SessionInfo>) {
-  const rows = sessions.map((session) => ({
-    id: session.id,
-    title: (session.title ?? "Untitled session").replace(/[\r\n\t]/g, " "),
-    updated: new Date(session.time.updated).toLocaleString(),
-  }))
-  const idWidth = Math.max(20, ...rows.map((row) => row.id.length))
-  const titleWidth = Math.max(25, ...rows.map((row) => row.title.length))
-  const header = `${"Session ID".padEnd(idWidth)}  ${"Title".padEnd(titleWidth)}  Updated`
-  return [
-    header,
-    "─".repeat(header.length),
-    ...rows.map((row) => `${row.id.padEnd(idWidth)}  ${row.title.padEnd(titleWidth)}  ${row.updated}`),
-  ].join(EOL)
+function formatList(sessions: ReadonlyArray<SessionInfo>) {
+  return sessions
+    .map((session) =>
+      [
+        session.id,
+        (session.title ?? "Untitled session").replace(/[\r\n\t]/g, " "),
+        new Date(session.time.updated).toLocaleString(),
+      ].join("\t"),
+    )
+    .join(EOL)
 }

packages/cli/test/acp/config-options.subprocess.test.ts

@@ -50,11 +50,11 @@ describe("acp config option subprocess", () => {
     const effort = requireSelectOption((await newSession(acp, fixture.home)).configOptions, "effort")
 
     expect(effort.category).toBe("thought_level")
-    expect(effort.currentValue).toBe("low")
-    expect(flattenSelectOptions(effort).map((option) => option.value)).toEqual(["low", "high"])
+    expect(effort.currentValue).toBe("default")
+    expect(flattenSelectOptions(effort).map((option) => option.value)).toEqual(["low", "high", "default"])
   }, 60_000)
 
-  test("effort switch updates currentValue", async () => {
+  test("effort survives model synchronization and can be reset to default", async () => {
     await using fixture = await createAcpFixture()
     const acp = fixture.spawn()
     await initialize(acp)
@@ -70,5 +70,23 @@ describe("acp config option subprocess", () => {
     )
 
     expect(selectConfigOption(updated.configOptions, "effort")?.currentValue).toBe(nextEffort)
+
+    const synchronized = expectOk(
+      await acp.request<SetSessionConfigOptionResponse>("session/set_config_option", {
+        sessionId: session.sessionId,
+        configId: "model",
+        value: requireSelectOption(session.configOptions, "model").currentValue,
+      }),
+    )
+    expect(selectConfigOption(synchronized.configOptions, "effort")?.currentValue).toBe(nextEffort)
+
+    const reset = expectOk(
+      await acp.request<SetSessionConfigOptionResponse>("session/set_config_option", {
+        sessionId: session.sessionId,
+        configId: "effort",
+        value: "default",
+      }),
+    )
+    expect(selectConfigOption(reset.configOptions, "effort")?.currentValue).toBe("default")
   }, 60_000)
 })

packages/cli/test/acp/event-behavior.test.ts

@@ -91,7 +91,7 @@ describe("acp event behavior", () => {
     }
   })
 
-  test("preserves text and reasoning order before returning the terminal response", async () => {
+  test("preserves reasoning boundaries and update order during streaming and replay", async () => {
     const firstUpdate = Promise.withResolvers<void>()
     const releaseUpdate = Promise.withResolvers<void>()
     const allUpdates = Promise.withResolvers<void>()
@@ -108,6 +108,14 @@ describe("acp event behavior", () => {
             delta: "think-1",
           }),
         )
+        send(
+          ephemeralEvent("session.reasoning.delta", {
+            sessionID: "ses_order",
+            assistantMessageID: "msg_order",
+            ordinal: 0,
+            delta: " continued",
+          }),
+        )
         send(
           ephemeralEvent("session.text.delta", {
             sessionID: "ses_order",
@@ -120,7 +128,7 @@ describe("acp event behavior", () => {
           ephemeralEvent("session.reasoning.delta", {
             sessionID: "ses_order",
             assistantMessageID: "msg_order",
-            ordinal: 2,
+            ordinal: 1,
             delta: "think-2",
           }),
         )
@@ -144,7 +152,7 @@ describe("acp event behavior", () => {
           firstUpdate.resolve()
           await releaseUpdate.promise
         }
-        if (updates.length === 3) allUpdates.resolve()
+        if (updates.length === 4) allUpdates.resolve()
       },
       requestPermission: async () => ({ outcome: { outcome: "cancelled" } }),
     } satisfies Connection
@@ -171,18 +179,48 @@ describe("acp event behavior", () => {
           ) {
             return [
               item.update.sessionUpdate,
+              item.update.messageId,
               item.update.content.type === "text" ? item.update.content.text : undefined,
             ]
           }
           return [item.update.sessionUpdate, undefined]
         }),
       ).toEqual([
-        ["agent_thought_chunk", "think-1"],
-        ["agent_message_chunk", "answer"],
-        ["agent_thought_chunk", "think-2"],
+        ["agent_thought_chunk", "msg_order:reasoning:0", "think-1"],
+        ["agent_thought_chunk", "msg_order:reasoning:0", " continued"],
+        ["agent_message_chunk", "msg_order", "answer"],
+        ["agent_thought_chunk", "msg_order:reasoning:1", "think-2"],
       ])
       expect(fixture.requests.at(-1)?.path).toBe("/api/session/ses_order/message/msg_order")
       expect(response).toMatchObject({ stopReason: "end_turn", usage: { totalTokens: 2 } })
+
+      const replayed: SessionUpdateParams[] = []
+      await replayMessages(recordingConnection(replayed), "ses_order", "/workspace", [
+        {
+          id: "msg_order",
+          type: "assistant",
+          agent: "build",
+          model: { providerID: "test", id: "test-model" },
+          time: { created: 1 },
+          content: [
+            { type: "reasoning", text: "think-1 continued" },
+            { type: "text", text: "answer" },
+            { type: "reasoning", text: "think-2" },
+          ],
+        },
+      ])
+      expect(replayed).toEqual([
+        {
+          sessionId: "ses_order",
+          update: {
+            sessionUpdate: "agent_thought_chunk",
+            messageId: "msg_order:reasoning:0",
+            content: { type: "text", text: "think-1 continued" },
+          },
+        },
+        updates[2],
+        updates[3],
+      ])
     } finally {
       releaseUpdate.resolve()
       releaseSubmit.resolve()

packages/cli/test/acp/service-directory.test.ts

@@ -222,7 +222,7 @@ describe("acp service directory behavior", () => {
     await fixture.service.setSessionMode({ sessionId: session.sessionId, modeId: "build" })
 
     expect(currentValue(selectedModel, "model")).toBe("test/second-model")
-    expect(currentValue(selectedModel, "effort")).toBe("low")
+    expect(currentValue(selectedModel, "effort")).toBe("default")
     expect(currentValue(selectedEffort, "effort")).toBe("medium")
     expect(currentValue(selectedMode, "mode")).toBe("plan")
     expect(

packages/cli/test/acp/service-lifecycle.test.ts

@@ -32,7 +32,7 @@ describe("acp service lifecycle", () => {
         model: { providerID: "test", id: "second-model" },
       },
     })
-    expect(currentValue(created, "effort")).toBe("none")
+    expect(currentValue(created, "effort")).toBe("default")
   })
 
   test("loads and forks with paginated replay while resume does not replay", async () => {

packages/client/src/effect/api/api.ts

@@ -11,13 +11,13 @@ import type { RelativePath } from "@opencode/schema/schema"
 import type { Brand } from "effect"
 import type { Model } from "@opencode/schema/model"
 import type { DateTime } from "effect"
+import type { Permission } from "@opencode/schema/permission"
 import type { SessionMessage } from "@opencode/schema/session-message"
 import type { SessionInbox } from "@opencode/schema/session-inbox"
 import type { PromptInput } from "@opencode/schema/prompt-input"
 import type { AgentAttachment } from "@opencode/schema/prompt"
 import type { Skill } from "@opencode/schema/skill"
 import type { Event } from "@opencode/schema/event"
-import type { FileDiff } from "@opencode/schema/file-diff"
 import type { InstructionEntry } from "@opencode/schema/instruction-entry"
 import type { Schema } from "effect"
 import type { EventLog } from "@opencode/schema/event-log"
@@ -27,7 +27,6 @@ import type { Integration } from "@opencode/schema/integration"
 import type { Form } from "@opencode/schema/form"
 import type { Mcp } from "@opencode/schema/mcp"
 import type { Credential } from "@opencode/schema/credential"
-import type { Permission } from "@opencode/schema/permission"
 import type { PermissionSaved } from "@opencode/schema/permission-saved"
 import type { FileSystem } from "@opencode/schema/filesystem"
 import type { Command } from "@opencode/schema/command"
@@ -37,6 +36,7 @@ import type { PtyTicket } from "@opencode/schema/pty-ticket"
 import type { Reference } from "@opencode/schema/reference"
 import type { Worktree } from "@opencode/schema/worktree"
 import type { Vcs } from "@opencode/schema/vcs"
+import type { FileDiff } from "@opencode/schema/file-diff"
 import type { WebSearch } from "@opencode/schema/websearch"
 import type { Config } from "@opencode/schema/config"
 
@@ -209,6 +209,7 @@ export type SessionCreateInput = {
   readonly model?: Model.Ref | undefined
   readonly location?: Location.Ref | undefined
   readonly metadata?: Session.Metadata | undefined
+  readonly permissions?: Permission.Ruleset | undefined
 }
 export type SessionCreateOutput = Session.Info
 export type SessionCreateOperation<E = never> = (input?: SessionCreateInput) => Effect.Effect<SessionCreateOutput, E>
@@ -360,15 +361,6 @@ export type SessionContextInput = { readonly sessionID: Session.ID }
 export type SessionContextOutput = ReadonlyArray<SessionMessage.Info>
 export type SessionContextOperation<E = never> = (input: SessionContextInput) => Effect.Effect<SessionContextOutput, E>
 
-export type SessionDiffInput = {
-  readonly sessionID: Session.ID
-  readonly messageID?: SessionMessage.ID | undefined
-  readonly to?: SessionMessage.ID | undefined
-  readonly context?: number | undefined
-}
-export type SessionDiffOutput = ReadonlyArray<FileDiff.Info>
-export type SessionDiffOperation<E = never> = (input: SessionDiffInput) => Effect.Effect<SessionDiffOutput, E>
-
 export type SessionInboxListInput = { readonly sessionID: Session.ID }
 export type SessionInboxListOutput = ReadonlyArray<SessionInbox.Info>
 export type SessionInboxListOperation<E = never> = (
@@ -446,6 +438,7 @@ export type SessionLogOutput =
             readonly agent?: Agent.ID | undefined
             readonly model?: Model.Ref | undefined
             readonly metadata?: Session.Metadata | undefined
+            readonly permissions?: Permission.Ruleset | undefined
             readonly version: string
           }
         }
@@ -498,6 +491,15 @@ export type SessionLogOutput =
           readonly location?: Location.Ref | undefined
           readonly data: { readonly sessionID: Session.ID; readonly title: string }
         }
+      | {
+          readonly id: Event.ID
+          readonly created: number
+          readonly metadata?: { readonly [x: string]: unknown } | undefined
+          readonly type: "session.permissions.updated"
+          readonly durable: { readonly aggregateID: string; readonly seq: Event.Seq; readonly version: Event.Version }
+          readonly location?: Location.Ref | undefined
+          readonly data: { readonly sessionID: Session.ID; readonly permissions: Permission.Ruleset }
+        }
       | {
           readonly id: Event.ID
           readonly created: number
@@ -1148,7 +1150,6 @@ export interface SessionApi<E = never> {
     readonly commit: SessionRevertCommitOperation<E>
   }
   readonly context: SessionContextOperation<E>
-  readonly diff: SessionDiffOperation<E>
   readonly inbox: {
     readonly list: SessionInboxListOperation<E>
     readonly cancel: SessionInboxCancelOperation<E>
@@ -1595,6 +1596,12 @@ export type PermissionReplyOperation<E = never> = (
   input: PermissionReplyInput,
 ) => Effect.Effect<PermissionReplyOutput, E>
 
+export type PermissionRulesInput = { readonly sessionID: Session.ID; readonly permissions: Permission.Ruleset }
+export type PermissionRulesOutput = void
+export type PermissionRulesOperation<E = never> = (
+  input: PermissionRulesInput,
+) => Effect.Effect<PermissionRulesOutput, E>
+
 export interface PermissionApi<E = never> {
   readonly request: { readonly list: PermissionRequestListOperation<E> }
   readonly saved: { readonly list: PermissionSavedListOperation<E>; readonly remove: PermissionSavedRemoveOperation<E> }
@@ -1602,6 +1609,7 @@ export interface PermissionApi<E = never> {
   readonly list: PermissionListOperation<E>
   readonly get: PermissionGetOperation<E>
   readonly reply: PermissionReplyOperation<E>
+  readonly rules: PermissionRulesOperation<E>
 }
 
 export type FileListInput = {

packages/client/src/effect/generated/client.ts

@@ -68,8 +68,6 @@ import type {
   SessionRevertCommitOutput,
   SessionContextInput,
   SessionContextOutput,
-  SessionDiffInput,
-  SessionDiffOutput,
   SessionInboxListInput,
   SessionInboxListOutput,
   SessionInboxCancelInput,
@@ -183,6 +181,8 @@ import type {
   PermissionGetOutput,
   PermissionReplyInput,
   PermissionReplyOutput,
+  PermissionRulesInput,
+  PermissionRulesOutput,
   FileListInput,
   FileListOutput,
   FileFindInput,
@@ -397,6 +397,7 @@ const EndpointSessionCreate = (raw: RawClient["server.session"]) => (input?: Ses
         model: input?.["model"],
         location: input?.["location"],
         metadata: input?.["metadata"],
+        permissions: input?.["permissions"],
       },
     }).pipe(
       Effect.mapError(mapClientError),
@@ -594,17 +595,6 @@ const EndpointSessionContext = (raw: RawClient["server.session"]) => (input: Ses
     ),
   )
 
-const EndpointSessionDiff = (raw: RawClient["server.session"]) => (input: SessionDiffInput) =>
-  preserveEffect<SessionDiffOutput>()(
-    raw["session.diff"]({
-      params: { sessionID: input["sessionID"] },
-      query: { messageID: input["messageID"], to: input["to"], context: input["context"] },
-    }).pipe(
-      Effect.mapError(mapClientError),
-      Effect.map((value) => value.data),
-    ),
-  )
-
 const EndpointSessionInboxList = (raw: RawClient["server.session"]) => (input: SessionInboxListInput) =>
   preserveEffect<SessionInboxListOutput>()(
     raw["session.inbox.list"]({ params: { sessionID: input["sessionID"] } }).pipe(
@@ -744,7 +734,6 @@ const adaptGroupSession = (raw: RawClient["server.session"]) => ({
     commit: EndpointSessionRevertCommit(raw),
   },
   context: EndpointSessionContext(raw),
-  diff: EndpointSessionDiff(raw),
   inbox: {
     list: EndpointSessionInboxList(raw),
     cancel: EndpointSessionInboxCancel(raw),
@@ -1159,6 +1148,14 @@ const EndpointPermissionReply = (raw: RawClient["server.permission"]) => (input:
     }).pipe(Effect.mapError(mapClientError)),
   )
 
+const EndpointPermissionRules = (raw: RawClient["server.permission"]) => (input: PermissionRulesInput) =>
+  preserveEffect<PermissionRulesOutput>()(
+    raw["session.permission.rules"]({
+      params: { sessionID: input["sessionID"] },
+      payload: { permissions: input["permissions"] },
+    }).pipe(Effect.mapError(mapClientError)),
+  )
+
 const adaptGroupPermission = (raw: RawClient["server.permission"]) => ({
   request: { list: EndpointPermissionRequestList(raw) },
   saved: { list: EndpointPermissionSavedList(raw), remove: EndpointPermissionSavedRemove(raw) },
@@ -1166,6 +1163,7 @@ const adaptGroupPermission = (raw: RawClient["server.permission"]) => ({
   list: EndpointPermissionList(raw),
   get: EndpointPermissionGet(raw),
   reply: EndpointPermissionReply(raw),
+  rules: EndpointPermissionRules(raw),
 })
 
 const EndpointFileList = (raw: RawClient["server.fs"]) => (input?: FileListInput) =>

packages/client/src/promise/generated/client.ts

@@ -62,8 +62,6 @@ import type {
   SessionRevertCommitOutput,
   SessionContextInput,
   SessionContextOutput,
-  SessionDiffInput,
-  SessionDiffOutput,
   SessionInboxListInput,
   SessionInboxListOutput,
   SessionInboxCancelInput,
@@ -177,6 +175,8 @@ import type {
   PermissionGetOutput,
   PermissionReplyInput,
   PermissionReplyOutput,
+  PermissionRulesInput,
+  PermissionRulesOutput,
   FileReadInput,
   FileReadOutput,
   FileListInput,
@@ -567,6 +567,7 @@ export function make(options: ClientOptions) {
               model: input?.["model"],
               location: input?.["location"],
               metadata: input?.["metadata"],
+              permissions: input?.["permissions"],
             },
             successStatus: 200,
             declaredStatuses: [400, 401],
@@ -844,18 +845,6 @@ export function make(options: ClientOptions) {
           },
           requestOptions,
         ).then((value) => value.data),
-      diff: (input: SessionDiffInput, requestOptions?: RequestOptions) =>
-        request<{ readonly data: SessionDiffOutput }>(
-          {
-            method: "GET",
-            path: `/api/session/${encodeURIComponent(input.sessionID)}/diff`,
-            query: { messageID: input["messageID"], to: input["to"], context: input["context"] },
-            successStatus: 200,
-            declaredStatuses: [400, 401, 404, 500],
-            empty: false,
-          },
-          requestOptions,
-        ).then((value) => value.data),
       inbox: {
         list: (input: SessionInboxListInput, requestOptions?: RequestOptions) =>
           request<{ readonly data: SessionInboxListOutput }>(
@@ -1580,6 +1569,18 @@ export function make(options: ClientOptions) {
           },
           requestOptions,
         ),
+      rules: (input: PermissionRulesInput, requestOptions?: RequestOptions) =>
+        request<PermissionRulesOutput>(
+          {
+            method: "PUT",
+            path: `/api/session/${encodeURIComponent(input.sessionID)}/permission/rules`,
+            body: { permissions: input["permissions"] },
+            successStatus: 204,
+            declaredStatuses: [400, 401, 404],
+            empty: true,
+          },
+          requestOptions,
+        ),
     },
     file: {
       read: (input: FileReadInput, requestOptions?: RequestOptions) =>

packages/client/src/promise/generated/types.ts

@@ -147,14 +147,6 @@ export type SessionProviderContextProvenance = {
   endpoint: string
 }
 
-export type SessionMessageIdle = {
-  id: string
-  metadata?: { [x: string]: JsonValue }
-  time: { created: number }
-  type: "idle"
-  outcome: "succeeded" | "failed" | "interrupted"
-}
-
 export type SessionActive = { type: "running" }
 
 export type SessionInboxDelivery = "steer" | "queue"
@@ -559,28 +551,6 @@ export type InstructionEntryInfo = { key: InstructionEntryKey; value: JsonValue
 
 export type InstructionEntrySnapshot = Array<{ key: InstructionEntryKey; value: JsonValue; removed: boolean }>
 
-export type SessionCreated = {
-  id: string
-  created: number
-  metadata?: { [x: string]: any }
-  type: "session.created"
-  durable: { aggregateID: string; seq: number; version: 1 }
-  location?: LocationRef
-  data: {
-    sessionID: string
-    projectID: string
-    location: LocationRef
-    subpath?: string
-    parentID?: string
-    slug: string
-    title?: string
-    agent?: string
-    model?: ModelRef
-    metadata?: SessionMetadata
-    version: string
-  }
-}
-
 export type SessionAgentSelected = {
   id: string
   created: number
@@ -1659,24 +1629,6 @@ export type SessionInboxMove = {
   delivery: SessionInboxDelivery
 }
 
-export type SessionInfo = {
-  id: string
-  parentID?: string
-  fork?: { sessionID: string; boundary: SessionForkBoundary }
-  projectID: string
-  agent?: string
-  model?: ModelRef
-  cost: MoneyUSD
-  tokens: TokenUsageInfo
-  outcome?: "succeeded" | "failed" | "interrupted"
-  time: { created: number; updated: number; idle?: number; viewed?: number; archived?: number }
-  title?: string
-  location: LocationRef
-  subpath?: string
-  metadata?: SessionMetadata
-  revert?: SessionRevert
-}
-
 export type SessionRevertStaged = {
   id: string
   created: number
@@ -1920,6 +1872,58 @@ export type AgentInfo = {
   permissions: PermissionRuleset
 }
 
+export type SessionPermissionsUpdated = {
+  id: string
+  created: number
+  metadata?: { [x: string]: any }
+  type: "session.permissions.updated"
+  durable: { aggregateID: string; seq: number; version: 1 }
+  location?: LocationRef
+  data: { sessionID: string; permissions: PermissionRuleset }
+}
+
+export type SessionInfo = {
+  id: string
+  parentID?: string
+  fork?: { sessionID: string; boundary: SessionForkBoundary }
+  projectID: string
+  agent?: string
+  model?: ModelRef
+  cost: MoneyUSD
+  tokens: TokenUsageInfo
+  outcome?: "succeeded" | "failed" | "interrupted"
+  time: { created: number; updated: number; idle?: number; viewed?: number; archived?: number }
+  title?: string
+  location: LocationRef
+  subpath?: string
+  metadata?: SessionMetadata
+  permissions?: PermissionRuleset
+  revert?: SessionRevert
+}
+
+export type SessionCreated = {
+  id: string
+  created: number
+  metadata?: { [x: string]: any }
+  type: "session.created"
+  durable: { aggregateID: string; seq: number; version: 1 }
+  location?: LocationRef
+  data: {
+    sessionID: string
+    projectID: string
+    location: LocationRef
+    subpath?: string
+    parentID?: string
+    slug: string
+    title?: string
+    agent?: string
+    model?: ModelRef
+    metadata?: SessionMetadata
+    permissions?: PermissionRuleset
+    version: string
+  }
+}
+
 export type ConfigEntry =
   | {
       type: "document"
@@ -2092,8 +2096,6 @@ export type ConfigEntry =
   | { type: "agents"; path: string }
   | { type: "claude"; path: string }
 
-export type SessionsResponse = { data: Array<SessionInfo>; cursor: { previous?: string | null; next?: string | null } }
-
 export type SessionInboxUser = {
   id: string
   sessionID: string
@@ -2148,6 +2150,8 @@ export type FormFields = [FormField, ...Array<FormField>]
 
 export type FormFields2 = [FormField1, ...Array<FormField1>]
 
+export type SessionsResponse = { data: Array<SessionInfo>; cursor: { previous?: string | null; next?: string | null } }
+
 export type SessionInboxInfo = SessionInboxUser | SessionInboxSynthetic | SessionInboxCompaction | SessionInboxMove
 
 export type SessionInboxEnqueued = {
@@ -2202,7 +2206,6 @@ export type SessionMessageInfo =
   | SessionMessageShell
   | SessionMessageAssistant
   | SessionMessageCompaction
-  | SessionMessageIdle
 
 export type SessionMessageContentUpdated = {
   id: string
@@ -2242,6 +2245,7 @@ export type SessionEventDurable =
   | SessionModelSelected
   | SessionMoved
   | SessionRenamed
+  | SessionPermissionsUpdated
   | SessionViewed
   | SessionDeleted
   | SessionForked
@@ -2301,6 +2305,7 @@ export type V2Event =
   | SessionModelSelected
   | SessionMoved
   | SessionRenamed
+  | SessionPermissionsUpdated
   | SessionViewed
   | SessionUsageUpdated
   | SessionDeleted
@@ -2813,6 +2818,11 @@ export type SessionCreateInput = {
     readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
     readonly metadata?: { readonly [x: string]: JsonValue } | null
+    readonly permissions?: ReadonlyArray<{
+      readonly action: string
+      readonly resource: string
+      readonly effect: "allow" | "deny" | "ask"
+    }> | null
   }["id"]
   readonly title?: {
     readonly id?: string | null
@@ -2821,6 +2831,11 @@ export type SessionCreateInput = {
     readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
     readonly metadata?: { readonly [x: string]: JsonValue } | null
+    readonly permissions?: ReadonlyArray<{
+      readonly action: string
+      readonly resource: string
+      readonly effect: "allow" | "deny" | "ask"
+    }> | null
   }["title"]
   readonly agent?: {
     readonly id?: string | null
@@ -2829,6 +2844,11 @@ export type SessionCreateInput = {
     readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
     readonly metadata?: { readonly [x: string]: JsonValue } | null
+    readonly permissions?: ReadonlyArray<{
+      readonly action: string
+      readonly resource: string
+      readonly effect: "allow" | "deny" | "ask"
+    }> | null
   }["agent"]
   readonly model?: {
     readonly id?: string | null
@@ -2837,6 +2857,11 @@ export type SessionCreateInput = {
     readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
     readonly metadata?: { readonly [x: string]: JsonValue } | null
+    readonly permissions?: ReadonlyArray<{
+      readonly action: string
+      readonly resource: string
+      readonly effect: "allow" | "deny" | "ask"
+    }> | null
   }["model"]
   readonly location?: {
     readonly id?: string | null
@@ -2845,6 +2870,11 @@ export type SessionCreateInput = {
     readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
     readonly metadata?: { readonly [x: string]: JsonValue } | null
+    readonly permissions?: ReadonlyArray<{
+      readonly action: string
+      readonly resource: string
+      readonly effect: "allow" | "deny" | "ask"
+    }> | null
   }["location"]
   readonly metadata?: {
     readonly id?: string | null
@@ -2853,7 +2883,25 @@ export type SessionCreateInput = {
     readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
     readonly metadata?: { readonly [x: string]: JsonValue } | null
+    readonly permissions?: ReadonlyArray<{
+      readonly action: string
+      readonly resource: string
+      readonly effect: "allow" | "deny" | "ask"
+    }> | null
   }["metadata"]
+  readonly permissions?: {
+    readonly id?: string | null
+    readonly title?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
+    readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
+    readonly metadata?: { readonly [x: string]: JsonValue } | null
+    readonly permissions?: ReadonlyArray<{
+      readonly action: string
+      readonly resource: string
+      readonly effect: "allow" | "deny" | "ask"
+    }> | null
+  }["permissions"]
 }
 
 export type SessionCreateOutput = { data: SessionInfo }["data"]
@@ -2891,6 +2939,11 @@ export type SessionImportInput = {
       readonly location: { readonly directory: string; readonly workspaceID?: string }
       readonly subpath?: string
       readonly metadata?: { readonly [x: string]: JsonValue }
+      readonly permissions?: ReadonlyArray<{
+        readonly action: string
+        readonly resource: string
+        readonly effect: "allow" | "deny" | "ask"
+      }>
       readonly revert?: {
         readonly messageID: string
         readonly partID?: string
@@ -3161,13 +3214,6 @@ export type SessionImportInput = {
               }
             }
         )
-      | {
-          readonly id: string
-          readonly metadata?: { readonly [x: string]: JsonValue }
-          readonly time: { readonly created: number }
-          readonly type: "idle"
-          readonly outcome: "succeeded" | "failed" | "interrupted"
-        }
     >
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
   }["info"]
@@ -3203,6 +3249,11 @@ export type SessionImportInput = {
       readonly location: { readonly directory: string; readonly workspaceID?: string }
       readonly subpath?: string
       readonly metadata?: { readonly [x: string]: JsonValue }
+      readonly permissions?: ReadonlyArray<{
+        readonly action: string
+        readonly resource: string
+        readonly effect: "allow" | "deny" | "ask"
+      }>
       readonly revert?: {
         readonly messageID: string
         readonly partID?: string
@@ -3473,13 +3524,6 @@ export type SessionImportInput = {
               }
             }
         )
-      | {
-          readonly id: string
-          readonly metadata?: { readonly [x: string]: JsonValue }
-          readonly time: { readonly created: number }
-          readonly type: "idle"
-          readonly outcome: "succeeded" | "failed" | "interrupted"
-        }
     >
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
   }["messages"]
@@ -3515,6 +3559,11 @@ export type SessionImportInput = {
       readonly location: { readonly directory: string; readonly workspaceID?: string }
       readonly subpath?: string
       readonly metadata?: { readonly [x: string]: JsonValue }
+      readonly permissions?: ReadonlyArray<{
+        readonly action: string
+        readonly resource: string
+        readonly effect: "allow" | "deny" | "ask"
+      }>
       readonly revert?: {
         readonly messageID: string
         readonly partID?: string
@@ -3785,13 +3834,6 @@ export type SessionImportInput = {
               }
             }
         )
-      | {
-          readonly id: string
-          readonly metadata?: { readonly [x: string]: JsonValue }
-          readonly time: { readonly created: number }
-          readonly type: "idle"
-          readonly outcome: "succeeded" | "failed" | "interrupted"
-        }
     >
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
   }["location"]
@@ -4281,27 +4323,6 @@ export type SessionContextInput = { readonly sessionID: { readonly sessionID: st
 
 export type SessionContextOutput = { data: Array<SessionMessageInfo> }["data"]
 
-export type SessionDiffInput = {
-  readonly sessionID: { readonly sessionID: string }["sessionID"]
-  readonly messageID?: {
-    readonly messageID?: string | undefined
-    readonly to?: string | undefined
-    readonly context?: number | undefined
-  }["messageID"]
-  readonly to?: {
-    readonly messageID?: string | undefined
-    readonly to?: string | undefined
-    readonly context?: number | undefined
-  }["to"]
-  readonly context?: {
-    readonly messageID?: string | undefined
-    readonly to?: string | undefined
-    readonly context?: number | undefined
-  }["context"]
-}
-
-export type SessionDiffOutput = { data: Array<FileDiffInfo> }["data"]
-
 export type SessionInboxListInput = { readonly sessionID: { readonly sessionID: string }["sessionID"] }
 
 export type SessionInboxListOutput = { data: Array<SessionInboxInfo> }["data"]
@@ -5804,6 +5825,19 @@ export type PermissionReplyInput = {
 
 export type PermissionReplyOutput = void
 
+export type PermissionRulesInput = {
+  readonly sessionID: { readonly sessionID: string }["sessionID"]
+  readonly permissions: {
+    readonly permissions: ReadonlyArray<{
+      readonly action: string
+      readonly resource: string
+      readonly effect: "allow" | "deny" | "ask"
+    }>
+  }["permissions"]
+}
+
+export type PermissionRulesOutput = void
+
 export type FileReadInput = {
   readonly location?: {
     readonly location?: { readonly directory?: string | undefined; readonly workspace?: string | undefined } | undefined

packages/client/src/solid/data.ts

@@ -695,6 +695,10 @@ export function createData(config: CreateDataInput) {
         })
         return
       }
+      case "session.permissions.updated":
+        if (store.session.info[event.data.sessionID])
+          setStore("session", "info", event.data.sessionID, "permissions", event.data.permissions)
+        return
       case "session.moved": {
         const current = store.session.info[event.data.sessionID]
         if (current) {
@@ -1024,18 +1028,6 @@ export function createData(config: CreateDataInput) {
           if (currentAssistant) currentAssistant.retry = undefined
         })
         if (event.type === "session.execution.interrupted" && event.data.reason === "shutdown") return
-        // Mirror the projected idle marker so turn boundaries match before the next message read.
-        message.insert(event.data.sessionID, {
-          id: messageIDFromEvent(event.id),
-          type: "idle",
-          outcome:
-            event.type === "session.execution.succeeded"
-              ? "succeeded"
-              : event.type === "session.execution.failed"
-                ? "failed"
-                : "interrupted",
-          time: { created: event.created },
-        })
         // An event can overtake the first read; queue a revalidation when that read is still active.
         if (!store.session.info[event.data.sessionID] && !sync.has(`session:${event.data.sessionID}`)) return
         result.session.invalidate(event.data.sessionID)

packages/codemode/src/stdlib/web.ts

@@ -5,9 +5,8 @@ import { coerceToString } from "./value.js"
 // WebIDL DOMString conversion: a missing argument is a TypeError, anything else stringifies.
 const base64 = (name: "atob" | "btoa") =>
   sync(name, (args, node) => {
-    if (args.length === 0) {
-      throw new InterpreterRuntimeError(`${name} requires 1 argument, but only 0 were provided.`, node).as("TypeError")
-    }
+    if (args.length === 0)
+      throw new InterpreterRuntimeError(`${name} requires 1 argument (a string)`, node).as("TypeError")
     const input = coerceToString(args[0])
     try {
       return name === "atob" ? atob(input) : btoa(input)

packages/core/src/aisdk.ts

@@ -547,6 +547,14 @@ function assistantPart(part: ContentPart): AssistantContent {
       ]
     case "tool-result":
       return toolResultPart(part)
+    case "effort":
+      throw ProviderShared.unsupportedContent("AI SDK", "assistant", [
+        "text",
+        "media",
+        "reasoning",
+        "tool-call",
+        "tool-result",
+      ])
   }
 }
 

packages/core/src/database/migration.gen.ts

@@ -45,6 +45,7 @@ import m42 from "./migration/20260812181746_session_inbox.js"
 import m43 from "./migration/20260812213948_worktree.js"
 import m44 from "./migration/20260819222447_session_viewed_state.js"
 import m45 from "./migration/20260823191254_nullable_workspace_binding.js"
+import m46 from "./migration/20260910120000_clear_v1_session_permission.js"
 
 export const migrations = [
   m00,
@@ -93,4 +94,5 @@ export const migrations = [
   m43,
   m44,
   m45,
+  m46,
 ] satisfies DatabaseMigration.Migration[]

packages/core/src/database/migration/20260910120000_clear_v1_session_permission.ts

@@ -0,0 +1,13 @@
+import { Effect } from "effect"
+import type { DatabaseMigration } from "../migration.js"
+
+const migration: DatabaseMigration.Migration = {
+  id: "20260910120000_clear_v1_session_permission",
+  up(tx) {
+    return Effect.gen(function* () {
+      yield* tx.run(`UPDATE \`session_v2\` SET \`permission\` = NULL;`)
+    })
+  },
+}
+
+export default migration

packages/core/src/database/v1-migration.bun.ts

@@ -600,7 +600,7 @@ export function run(options: Options = {}): Effect.Effect<RunResult, never, Data
                     id, ${projectID}, workspace_id, parent_id, slug, directory, path, title, version, share_url,
                     summary_additions, summary_deletions, summary_files, summary_diffs, metadata, cost,
                     tokens_input, tokens_output, tokens_reasoning, tokens_cache_read, tokens_cache_write,
-                    revert, permission, agent, model, time_created, time_updated, time_compacting, time_archived
+                    revert, NULL, agent, model, time_created, time_updated, time_compacting, time_archived
                   FROM session
                   WHERE id = ${nextID.id}
                 `)

packages/core/src/generate.ts

@@ -41,6 +41,8 @@ export const layer = Layer.effect(
           [
             "SessionRunnerModel.VariantUnavailableError",
             "SessionRunnerModel.UnsupportedPackageError",
+            "SessionRunnerModel.ModelConfigurationError",
+            "SessionRunnerModel.ModelInitializationError",
             "SessionRunnerModel.UnresolvedProviderVariablesError",
             "SessionRunnerModel.UnsupportedCompactionError",
           ],

packages/core/src/git.ts

@@ -9,7 +9,6 @@ import { AppProcess } from "@opencode/util/process"
 import { makeGlobalNode } from "@opencode/util/effect/app-node"
 import { File } from "./file.js"
 import { KeyedMutex } from "./effect/keyed-mutex.js"
-import { VcsPatch } from "./vcs/patch.js"
 
 export class Repository extends Schema.Class<Repository>("Git.Repository")({
   worktree: AbsolutePath,
@@ -309,7 +308,7 @@ const layer = Layer.effect(
       operationName: OperationError["operation"],
       repository: Repository,
       args: string[],
-      options?: { stdin?: string; env?: Record<string, string>; maxOutputBytes?: number },
+      options?: { stdin?: string; env?: Record<string, string> },
     ) {
       const result = yield* proc
         .run(
@@ -318,7 +317,7 @@ const layer = Layer.effect(
             env: options?.env,
             extendEnv: true,
           }),
-          { stdin: options?.stdin, maxOutputBytes: options?.maxOutputBytes },
+          { stdin: options?.stdin },
         )
         .pipe(
           Effect.mapError(
@@ -332,8 +331,7 @@ const layer = Layer.effect(
           ),
         )
       const text = result.stdout.toString("utf8")
-      if (result.exitCode === 0)
-        return { text, stderr: result.stderr.toString("utf8"), truncated: result.stdoutTruncated }
+      if (result.exitCode === 0) return { text, stderr: result.stderr.toString("utf8") }
       return yield* new OperationError({
         operation: operationName,
         directory: repository.worktree,
@@ -387,7 +385,9 @@ const layer = Layer.effect(
       maximumUntrackedFileBytes?: number
     }) {
       const list = (args: string[]) =>
-        repositoryOperation("refresh", input.repository, args).pipe(Effect.map((result) => nuls(result.text)))
+        repositoryOperation("refresh", input.repository, args).pipe(
+          Effect.map((result) => result.text.split("\0").filter(Boolean)),
+        )
       const [tracked, untracked] = yield* Effect.all(
         [
           list(["diff-files", "--name-only", "-z", "--", input.scope]),
@@ -464,7 +464,13 @@ const layer = Layer.effect(
           directory: input.repository.worktree,
           message: result.stderr.toString("utf8").trim() || "Failed to check ignored paths",
         })
-      return new Set(nuls(result.stdout.toString("utf8")).map((file) => RelativePath.make(file)))
+      return new Set(
+        result.stdout
+          .toString("utf8")
+          .split("\0")
+          .filter(Boolean)
+          .map((file) => RelativePath.make(file)),
+      )
     })
 
     const writeTree = Effect.fn("Git.tree.write")(function* (repository: Repository) {
@@ -493,23 +499,19 @@ const layer = Layer.effect(
       to: TreeID
     }) {
       // Undo needs both paths of a rename, not only its destination.
-      return nuls(
-        (yield* repositoryOperation("list_files", input.repository, [
-          "diff",
-          "--name-only",
-          "--no-renames",
-          "-z",
-          input.from,
-          input.to,
-        ])).text,
-      ).map((file) => RelativePath.make(file))
+      return (yield* repositoryOperation("list_files", input.repository, [
+        "diff",
+        "--name-only",
+        "--no-renames",
+        "-z",
+        input.from,
+        input.to,
+      ])).text
+        .split("\0")
+        .filter(Boolean)
+        .map((file) => RelativePath.make(file))
     })
 
-    /**
-     * Three batched invocations over the tree pair instead of three per file. An
-     * explicit empty selection diffs nothing; an absent one diffs every changed path.
-     * Patch output is capped like VCS diffs: files past the cap get an empty patch.
-     */
     const treeDiff = Effect.fn("Git.tree.diff")(function* (input: {
       repository: Repository
       from: TreeID
@@ -517,57 +519,49 @@ const layer = Layer.effect(
       context?: number
       paths?: readonly RelativePath[]
     }) {
-      if (input.paths?.length === 0) return []
-      const args = ["--no-renames", input.from, input.to, "--", ...(input.paths ?? [])]
-      // Patch headers have no -z form: unquoted paths keep chunksByFile matching non-ASCII names.
-      const [names, numbers, patch] = yield* Effect.all(
-        [
-          repositoryOperation("diff", input.repository, ["diff", "--name-status", "-z", ...args]),
-          repositoryOperation("diff", input.repository, ["diff", "--numstat", "-z", ...args]),
-          repositoryOperation(
+      const paths = input.paths ?? (yield* treeFiles(input))
+      return yield* Effect.forEach(paths, (file) =>
+        Effect.gen(function* () {
+          const statusText = (yield* repositoryOperation("diff", input.repository, [
             "diff",
-            input.repository,
-            ["-c", "core.quotepath=false", "diff", "--no-ext-diff", `--unified=${input.context ?? 3}`, ...args],
-            { maxOutputBytes: VcsPatch.MAX_TOTAL_PATCH_BYTES },
-          ),
-        ],
-        { concurrency: 3 },
-      )
-      const statuses = nuls(names.text)
-      const files = statuses.flatMap((code, index) => {
-        const file = statuses[index + 1]
-        if (index % 2 !== 0 || !file) return []
-        return [
-          {
-            file: RelativePath.make(file),
-            status: code.startsWith("A") ? "added" : code.startsWith("D") ? "deleted" : "modified",
-          } as const,
-        ]
-      })
-      const stats = new Map(
-        nuls(numbers.text).flatMap((line) => {
-          const [additions, deletions, ...file] = line.split("\t")
-          if (!additions || !deletions || file.length === 0) return []
-          return [
-            [
-              file.join("\t"),
-              additions === "-" || deletions === "-"
-                ? { binary: true, additions: 0, deletions: 0 }
-                : { binary: false, additions: Number(additions), deletions: Number(deletions) },
-            ] as const,
-          ]
+            "--name-status",
+            "--no-renames",
+            input.from,
+            input.to,
+            "--",
+            file,
+          ])).text.trim()
+          const status = statusText.startsWith("A") ? "added" : statusText.startsWith("D") ? "deleted" : "modified"
+          const stats = (yield* repositoryOperation("diff", input.repository, [
+            "diff",
+            "--numstat",
+            "--no-renames",
+            input.from,
+            input.to,
+            "--",
+            file,
+          ])).text.split("\t")
+          const binary = stats[0] === "-" || stats[1] === "-"
+          const patch = binary
+            ? ""
+            : (yield* repositoryOperation("diff", input.repository, [
+                "diff",
+                `--unified=${input.context ?? 3}`,
+                "--no-renames",
+                input.from,
+                input.to,
+                "--",
+                file,
+              ])).text
+          return {
+            file,
+            status,
+            additions: binary ? 0 : Number(stats[0] ?? 0),
+            deletions: binary ? 0 : Number(stats[1] ?? 0),
+            patch,
+          } satisfies File.Diff
         }),
       )
-      const patches = VcsPatch.chunksByFile(patch, (index) => files[index]?.file)
-      return files.map((entry) => {
-        const stat = stats.get(entry.file)
-        return {
-          ...entry,
-          additions: stat?.additions ?? 0,
-          deletions: stat?.deletions ?? 0,
-          patch: stat?.binary ? "" : (patches.get(entry.file) ?? VcsPatch.emptyPatch(entry.file)),
-        } satisfies File.Diff
-      })
     })
 
     const hasEntry = Effect.fnUntraced(function* (repository: Repository, tree: TreeID, file: RelativePath) {
@@ -739,11 +733,6 @@ function execute(cwd: string, proc: AppProcess.Interface, args: string[]) {
     )
 }
 
-/** Split NUL-terminated git output into its records. */
-function nuls(text: string) {
-  return text.split("\0").filter(Boolean)
-}
-
 function resolvePath(cwd: string, value: string) {
   const trimmed = value.replace(/[\r\n]+$/, "")
   if (!trimmed) return cwd

packages/core/src/model-resolver.ts

@@ -1,7 +1,7 @@
 export * as ModelResolver from "./model-resolver.js"
 
 import { makeLocationNode } from "@opencode/util/effect/app-node"
-import { LanguageModel } from "@opencode/ai"
+import { LanguageModel, ProviderConfigurationError } from "@opencode/ai"
 import { Auth } from "@opencode/ai/route"
 import { Context, Effect, Layer, Schema, Struct } from "effect"
 import { AISDK } from "./aisdk.js"
@@ -39,6 +39,40 @@ export class UnsupportedPackageError extends Schema.TaggedError<UnsupportedPacka
   }
 }
 
+export const InitializationPhase = Schema.Literals(["load", "init", "construct"])
+export type InitializationPhase = typeof InitializationPhase.Type
+
+/** Provider settings are missing, conflicting, or unsupported; the provider's own message tells the user what to fix. */
+export class ModelConfigurationError extends Schema.TaggedError<ModelConfigurationError>()(
+  "SessionRunnerModel.ModelConfigurationError",
+  {
+    providerID: Provider.ID,
+    modelID: ID,
+    package: Schema.String,
+    detail: Schema.String,
+  },
+) {
+  override get message() {
+    return `Cannot initialize ${this.providerID}/${this.modelID}: ${this.detail}`
+  }
+}
+
+/** A supported package failed unexpectedly while loading or constructing the model. */
+export class ModelInitializationError extends Schema.TaggedError<ModelInitializationError>()(
+  "SessionRunnerModel.ModelInitializationError",
+  {
+    providerID: Provider.ID,
+    modelID: ID,
+    package: Schema.String,
+    phase: InitializationPhase,
+    detail: Schema.String,
+  },
+) {
+  override get message() {
+    return `Cannot initialize ${this.providerID}/${this.modelID}: ${this.detail}`
+  }
+}
+
 export class UnresolvedProviderVariablesError extends Schema.TaggedError<UnresolvedProviderVariablesError>()(
   "SessionRunnerModel.UnresolvedProviderVariablesError",
   {
@@ -68,6 +102,8 @@ export class UnsupportedCompactionError extends Schema.TaggedError<UnsupportedCo
 export type Error =
   | VariantUnavailableError
   | UnsupportedPackageError
+  | ModelConfigurationError
+  | ModelInitializationError
   | UnresolvedProviderVariablesError
   | UnsupportedCompactionError
   | Integration.AuthorizationError
@@ -135,7 +171,11 @@ export const fromCatalogModel = (
   dependencies?: Dependencies,
 ): Effect.Effect<
   LanguageModel,
-  UnsupportedPackageError | UnresolvedProviderVariablesError | UnsupportedCompactionError
+  | UnsupportedPackageError
+  | ModelConfigurationError
+  | ModelInitializationError
+  | UnresolvedProviderVariablesError
+  | UnsupportedCompactionError
 > =>
   resolveCatalogModel(model, credential, dependencies).pipe(
     Effect.flatMap((resolved) => validateProviderVariables(model, resolved)),
@@ -178,14 +218,16 @@ const resolveCatalogModel = Effect.fn("ModelResolver.resolveCatalogModel")(funct
         ...configuration,
       }) ?? {},
     )
-    return yield* loadAISDK({ ...resolved, settings }).pipe(Effect.mapError(() => unsupported(resolved)))
+    return yield* loadAISDK({ ...resolved, settings }).pipe(
+      Effect.mapError((error) => initialization(resolved, "init", error.cause)),
+    )
   }
   if (!native) return yield* unsupported(resolved)
 
   const specifier = native
   const mapped = yield* prepareProviderSettings(resolved, mapping?.settings ?? configured)
   const module = yield* (dependencies?.loadPackage ?? Provider.loadPackage)(specifier).pipe(
-    Effect.mapError(() => unsupported(resolved)),
+    Effect.mapError((error) => initialization(resolved, "load", error.cause)),
   )
   const settings = {
     ...(credential ? Struct.omit(mapped, ["accessToken", "apiKey", "authToken"]) : mapped),
@@ -204,7 +246,15 @@ const resolveCatalogModel = Effect.fn("ModelResolver.resolveCatalogModel")(funct
           : runtime.compatibility,
       })
     },
-    catch: () => unsupported(resolved),
+    catch: (cause) =>
+      cause instanceof ProviderConfigurationError
+        ? new ModelConfigurationError({
+            providerID: resolved.providerID,
+            modelID: resolved.id,
+            package: resolved.package ?? "unknown",
+            detail: cause.message,
+          })
+        : initialization(resolved, "construct", cause),
   })
 })
 
@@ -277,6 +327,24 @@ const unsupported = (model: Info) =>
     package: model.package ?? "unknown",
   })
 
+const initialization = (model: Info, phase: InitializationPhase, cause: unknown) =>
+  new ModelInitializationError({
+    providerID: model.providerID,
+    modelID: model.id,
+    package: model.package ?? "unknown",
+    phase,
+    detail: causeMessage(cause) ?? `${phase} failed for ${model.package ?? "unknown"}`,
+  })
+
+// Unexpected throws still carry the most useful diagnosis in their message; a stack or an unknown value does not.
+const causeMessage = (cause: unknown): string | undefined => {
+  if (typeof cause === "string") return cause.trim() || undefined
+  if (!(cause instanceof globalThis.Error)) return undefined
+  const message = cause.message.trim()
+  if (message) return message
+  return causeMessage(cause.cause)
+}
+
 export const resolveModel = (
   model: Info,
   variant: VariantID | undefined,

packages/core/src/permission.ts

@@ -154,7 +154,7 @@ const layer = Layer.effect(
       const session = yield* sessions.get(sessionID)
       if (!session) return yield* new SessionErrors.NotFoundError({ sessionID })
       const agent = yield* agents.resolve(agentID ?? session.agent)
-      return agent?.permissions ?? missingAgentPermissions
+      return merge(agent?.permissions ?? missingAgentPermissions, session.permissions ?? [])
     })
 
     function denied(input: Pick<Request, "action" | "resources">, rules: Permission.Ruleset) {

packages/core/src/plugin/host.ts

@@ -404,6 +404,7 @@ export const make = Effect.fn("PluginHost.make")(function* (
                 : Effect.fail(new Error(`Permission request not found: ${input.requestID}`)),
             ),
           ),
+      rules: sessions.setPermissions,
     },
     plugin: {
       list: () => response(plugin.list()),
@@ -509,6 +510,8 @@ export const make = Effect.fn("PluginHost.make")(function* (
           title: input?.title,
           agent: input?.agent,
           model: input?.model,
+          metadata: input?.metadata,
+          permissions: input?.permissions,
           location:
             input?.location ?? Location.Ref.make({ directory: location.directory, workspaceID: location.workspaceID }),
         }),

packages/core/src/plugin/optimize.ts

@@ -11,6 +11,7 @@ import PROMPT_ASTRA from "./system-prompt/gpt-astra.txt"
 import PROMPT_KIMI from "./system-prompt/kimi.txt"
 import PROMPT_META from "./system-prompt/meta.txt"
 import PROMPT_TRINITY from "./system-prompt/trinity.txt"
+import PROMPT_ANTHROPIC from "./system-prompt/anthropic.txt"
 
 export const OpenAIPlugin = make("opencode.prompt.openai", (model) => {
   const id = model.id.toLowerCase()
@@ -18,6 +19,19 @@ export const OpenAIPlugin = make("opencode.prompt.openai", (model) => {
   return id.includes("gpt-6") ? PROMPT_ASTRA : PROMPT_GPT
 })
 
+export const AnthropicPlugin = make(
+  "opencode.prompt.anthropic",
+  (model) => {
+    const id = model.id.toLowerCase()
+    if (!id.includes("claude")) return undefined
+    return PROMPT_ANTHROPIC
+  },
+  "append",
+)
+
+// Both OpenAIToolsPlugin and AnthropicToolsPlugin are disabled intentionally until we can figure out a good ux for displaying
+// heavy grep/glob usage done via shell or other mechanisms
+
 export const OpenAIToolsPlugin = make("opencode.optimize.openai.tools", (model, tools) => {
   const ids = [model.id, model.modelID, model.family].join(" ").toLowerCase()
   if (!ids.includes("gpt")) return undefined
@@ -45,11 +59,12 @@ export const MetaPlugin = make("opencode.prompt.meta", (model) => {
   return PROMPT_META.replaceAll("{{MODEL_NAME}}", model.name)
 })
 
-export const Plugins = [OpenAIPlugin, KimiPlugin, ArceePlugin, MetaPlugin] as const
+export const Plugins = [OpenAIPlugin, AnthropicPlugin, KimiPlugin, ArceePlugin, MetaPlugin] as const
 
 function make(
   id: string,
   optimize: (model: Model.Info, tools: SessionHooks["context"]["tools"]) => string | undefined,
+  mode: "override" | "append" = "override",
 ) {
   return define({
     id,
@@ -66,7 +81,9 @@ function make(
           if ((yield* ctx.agent.get({ agentID: event.agent })).data.system) return
           const system = event.system[0]
           if (!system) return
-          event.system[0] = { ...system, text: SessionSystemPrompt.render(template, Object.keys(event.tools)) }
+          const rendered = SessionSystemPrompt.render(template, Object.keys(event.tools))
+          const text = mode === "append" ? `${system.text}\n\n${rendered}` : rendered
+          event.system[0] = { ...system, text }
         }).pipe(Effect.catch(() => Effect.void))
       yield* ctx.session.hook("context", hook)
       yield* ctx.session.hook("compaction", hook)

packages/core/src/plugin/provider/xai.ts

@@ -101,6 +101,7 @@ export const XAIPlugin = define({
       for (const model of provider.models.values()) {
         catalog.model.update(providerID, model.id, (draft) => {
           draft.capabilities.responsesWebsockets = true
+          draft.websocket = true
         })
       }
     })

packages/core/src/plugin/system-prompt/anthropic.txt

@@ -0,0 +1,2 @@
+# Code comments
+By default, match the surrounding comment density: where the code has none, add none. Use comments sparingly, only where they are appropriate, such as for behavior that is not obvious from the code itself. Instructions from the user or the project take precedence over this guidance.

packages/core/src/session.ts

@@ -18,6 +18,7 @@ import { SessionMessageTable } from "./session/sql.js"
 import { SessionSchema } from "./session/schema.js"
 import { RelativePath } from "./schema.js"
 import { Agent } from "@opencode/schema/agent"
+import type { Permission } from "@opencode/schema/permission"
 import { App } from "./app.js"
 import { Slug } from "./util/slug.js"
 import path from "path"
@@ -54,11 +55,8 @@ import { SessionModelTransport } from "./session/model-transport.js"
 import { llmClient } from "./effect/app-node-platform.js"
 import { Snapshot } from "./snapshot.js"
 import { Session } from "./session/session.js"
-import { SessionDiff, TurnRangeError } from "./session/diff.js"
-import { LocationServiceMap } from "./location-service-map.js"
 import { FSUtil } from "@opencode/util/fs-util"
 import type { EventLog } from "@opencode/schema/event-log"
-import type { FileDiff } from "@opencode/schema/file-diff"
 import { Job } from "./job.js"
 import type { Command } from "./command.js"
 import { SessionEnvironment } from "./session/environment.js"
@@ -84,6 +82,7 @@ type CreateBaseInput = {
   agent?: Agent.ID
   model?: Model.Ref
   metadata?: SessionSchema.Metadata
+  permissions?: Permission.Ruleset
 }
 type CreateInput = CreateBaseInput &
   ({ location: Location.Ref; parentID?: never } | { parentID: SessionSchema.ID; location?: never })
@@ -110,7 +109,6 @@ export {
 type InboxItemRef = { readonly sessionID: SessionSchema.ID; readonly inboxID: SessionMessage.ID }
 
 export { DestinationNotFoundError, DestinationNotDirectoryError, DestinationUnavailableError }
-export { TurnRangeError }
 
 export interface Interface {
   readonly list: (input?: ListInput) => Effect.Effect<{
@@ -137,13 +135,6 @@ export interface Interface {
   readonly context: (
     sessionID: SessionSchema.ID,
   ) => Effect.Effect<SessionMessage.Info[], NotFoundError | MessageDecodeError>
-  /** Structured diffs of the files changed by a turn or range of turns; see `SessionDiff.turn`. */
-  readonly diff: (input: {
-    readonly sessionID: SessionSchema.ID
-    readonly messageID?: SessionMessage.ID
-    readonly to?: SessionMessage.ID
-    readonly context?: number
-  }) => Effect.Effect<readonly FileDiff.Info[], NotFoundError | MessageNotFoundError | TurnRangeError | Snapshot.Error>
   /**
    * Durable admitted session work not yet visible in projected history,
    * ordered by admission. Includes unpromoted user and synthetic inputs and
@@ -168,6 +159,10 @@ export interface Interface {
   readonly switchAgent: (input: { sessionID: SessionSchema.ID; agent: Agent.ID }) => Effect.Effect<void, NotFoundError>
   readonly switchModel: (input: { sessionID: SessionSchema.ID; model: Model.Ref }) => Effect.Effect<void, NotFoundError>
   readonly rename: (input: { sessionID: SessionSchema.ID; title: string }) => Effect.Effect<void, NotFoundError>
+  readonly setPermissions: (input: {
+    sessionID: SessionSchema.ID
+    permissions: Permission.Ruleset
+  }) => Effect.Effect<void, NotFoundError>
   readonly move: SessionMove.Interface["move"]
   readonly prompt: (
     input: Parameters<Session.Handle["prompt"]>[0] & { sessionID: SessionSchema.ID },
@@ -232,7 +227,6 @@ const layer = Layer.effect(
     const moves = yield* SessionMove.Service
     const jobs = yield* Job.Service
     const environments = yield* SessionEnvironment.Service
-    const locations = yield* LocationServiceMap.Service
     const sessions = yield* Session.make()
     const isDurableSessionEvent = Schema.is(SessionEvent.Durable)
 
@@ -260,9 +254,10 @@ const layer = Layer.effect(
               subpath: RelativePath.make(path.relative(project.directory, location.directory).replaceAll("\\", "/")),
               title: input.title,
               agent: input.agent,
-              // Children inherit metadata the way they inherit location, so
-              // host policies that read it treat the family uniformly.
+              // Children inherit metadata and permissions the way they inherit
+              // location, so host policies that read them treat the family uniformly.
               metadata: input.metadata ?? parent?.metadata,
+              permissions: input.permissions ?? parent?.permissions,
               model: input.model
                 ? {
                     id: Model.ID.make(input.model.id),
@@ -364,17 +359,6 @@ const layer = Layer.effect(
         yield* result.get(sessionID)
         return yield* store.context(sessionID)
       }),
-      diff: Effect.fn("Session.diff")(function* (input) {
-        const session = yield* result.get(input.sessionID)
-        const active = yield* execution.isActive(input.sessionID)
-        return yield* SessionDiff.turn(db, locations, {
-          session,
-          active,
-          messageID: input.messageID,
-          to: input.to,
-          context: input.context,
-        })
-      }),
       inbox: (sessionID) => sessions.forSession(sessionID).inbox(),
       cancelInbox: (input) => sessions.forSession(input.sessionID).cancelInbox(input.inboxID),
       steerInbox: (input) => sessions.forSession(input.sessionID).steerInbox(input.inboxID),
@@ -410,6 +394,7 @@ const layer = Layer.effect(
       switchAgent: (input) => sessions.forSession(input.sessionID).switchAgent(input),
       switchModel: (input) => sessions.forSession(input.sessionID).switchModel(input),
       rename: (input) => sessions.forSession(input.sessionID).rename(input),
+      setPermissions: (input) => sessions.forSession(input.sessionID).setPermissions(input),
       move: moves.move,
       compact: (input) => sessions.forSession(input.sessionID).compact(input),
       wait: (sessionID) => sessions.forSession(sessionID).wait(),
@@ -463,7 +448,6 @@ export const node: LayerNode.Provider<Service, never, typeof Node.tags.values.gl
     SessionInbox.node,
     SessionMove.node,
     SessionProjector.node,
-    LocationServiceMap.node,
     FSUtil.node,
     App.node,
   ],

packages/core/src/session/compaction.ts

@@ -196,6 +196,7 @@ const estimateMedia = (mime: string) => {
 const estimatePart = (part: ContentPart): number => {
   // Encrypted checkpoints have no locally measurable token size.
   if (part.type === "compaction") return Token.estimate(part.text ?? "")
+  if (part.type === "effort") return 0
   if (part.type === "text" || part.type === "reasoning") return Token.estimate(part.text)
   if (part.type === "media") return estimateMedia(part.mediaType)
   if (part.type === "tool-call") return Token.estimate(part.name + (JSON.stringify(part.input) ?? ""))

packages/core/src/session/context.ts

@@ -1,6 +1,7 @@
 export * as SessionContext from "./context.js"
 
 import { Model } from "@opencode/schema/model"
+import { Permission } from "../permission.js"
 import { Context, Effect, Layer } from "effect"
 import { Agent } from "../agent.js"
 import { Catalog } from "../catalog.js"
@@ -129,7 +130,7 @@ const layer = Layer.effect(
       if (!agent.info) return yield* new AgentNotFoundError({ sessionID: session.id, agent: session.agent ?? agent.id })
       const loaded = yield* Effect.all(
         {
-          tools: registry.snapshot(agent.info.permissions),
+          tools: registry.snapshot(Permission.merge(agent.info.permissions, session.permissions ?? [])),
           builtins: builtins.load(sessionID),
           discovery: discovery.load(),
           skills: skillInstructions.load(agent),

packages/core/src/session/diff.ts

@@ -1,138 +0,0 @@
-export * as SessionDiff from "./diff.js"
-
-import { and, asc, eq, gt, inArray, lt, or, sql } from "drizzle-orm"
-import { Context, Effect, Schema } from "effect"
-import { Location } from "@opencode/schema/location"
-import { Database } from "../database/database.js"
-import { LocationServiceMap } from "../location-service-map.js"
-import { Snapshot } from "../snapshot.js"
-import { PATCH_CONTEXT_LINES } from "../vcs/patch.js"
-import { MessageNotFoundError } from "./error.js"
-import { SessionMessage } from "./message.js"
-import { SessionSchema } from "./schema.js"
-import { SessionMessageTable } from "./sql.js"
-
-export class TurnRangeError extends Schema.TaggedError<TurnRangeError>()("Session.TurnRangeError", {
-  sessionID: SessionSchema.ID,
-  field: Schema.Literals(["messageID", "to"]),
-  message: Schema.String,
-}) {}
-
-const decodeLocation = Schema.decodeUnknownSync(Schema.fromJsonString(Location.Ref))
-
-/**
- * Diff the files changed by the turn containing a user message. A turn runs from
- * the first prompt after the Session was last idle until the next idle marker, so
- * prompts steered in while it was busy belong to the same turn; `to` extends the
- * range through the turn containing a later user message. Compares the range's
- * first recorded start snapshot with its last recorded end snapshot; only a step
- * still running in the active Session compares against the working copy. Like VCS
- * diffs, an omitted `context` yields full-file patches.
- *
- * A Session without any idle marker predates them, so its prompts span until the
- * next user message instead.
- *
- * Snapshot trees live in the repository of the Location that captured them, so a
- * range spanning a location switch is rejected rather than diffed wrongly.
- */
-export const turn = Effect.fn("SessionDiff.turn")(function* (
-  db: Database.Interface["db"],
-  locations: Context.Service.Shape<typeof LocationServiceMap.Service>,
-  input: {
-    readonly session: SessionSchema.Info
-    /** The process is currently executing this Session. */
-    readonly active: boolean
-    readonly messageID?: SessionMessage.ID
-    readonly to?: SessionMessage.ID
-    readonly context?: number
-  },
-) {
-  const sessionID = input.session.id
-  const rows = yield* db
-    .select({ id: SessionMessageTable.id, type: SessionMessageTable.type, seq: SessionMessageTable.seq })
-    .from(SessionMessageTable)
-    .where(
-      and(
-        eq(SessionMessageTable.session_id, sessionID),
-        or(
-          inArray(SessionMessageTable.type, ["user", "idle"]),
-          input.messageID ? eq(SessionMessageTable.id, input.messageID) : undefined,
-          input.to ? eq(SessionMessageTable.id, input.to) : undefined,
-        ),
-      ),
-    )
-    .orderBy(asc(SessionMessageTable.seq))
-    .all()
-    .pipe(Effect.orDie)
-  const users = rows.filter((row) => row.type === "user")
-  const markers = rows.filter((row) => row.type === "idle")
-  const resolve = Effect.fn(function* (field: "messageID" | "to", id: SessionMessage.ID) {
-    const row = rows.find((row) => row.id === id)
-    if (!row) return yield* new MessageNotFoundError({ sessionID, messageID: id })
-    if (row.type !== "user")
-      return yield* new TurnRangeError({ sessionID, field, message: `Message ${id} is not a user message` })
-    return row
-  })
-  const anchor = input.messageID ? yield* resolve("messageID", input.messageID) : users[users.length - 1]
-  if (!anchor) return []
-  const last = input.to ? yield* resolve("to", input.to) : anchor
-  if (last.seq < anchor.seq)
-    return yield* new TurnRangeError({ sessionID, field: "to", message: `Message ${last.id} precedes ${anchor.id}` })
-  // Without any marker, history predates idle markers and a prompt's turn ends at the next prompt.
-  const legacy = markers.length === 0
-  // The turn opens with the first prompt after the previous idle marker; the anchor itself is the latest candidate.
-  const opened = markers.findLast((row) => row.seq < anchor.seq)?.seq ?? -1
-  const start = legacy ? anchor.seq : (users.find((row) => row.seq > opened)?.seq ?? anchor.seq)
-  const end = legacy ? users.find((row) => row.seq > last.seq)?.seq : markers.find((row) => row.seq > last.seq)?.seq
-  const steps = yield* db
-    .select({
-      seq: SessionMessageTable.seq,
-      start: sql<string | null>`json_extract(${SessionMessageTable.data}, '$.snapshot.start')`,
-      end: sql<string | null>`json_extract(${SessionMessageTable.data}, '$.snapshot.end')`,
-      completed: sql<number | null>`json_extract(${SessionMessageTable.data}, '$.time.completed')`,
-    })
-    .from(SessionMessageTable)
-    .where(
-      and(
-        eq(SessionMessageTable.session_id, sessionID),
-        eq(SessionMessageTable.type, "assistant"),
-        gt(SessionMessageTable.seq, start),
-        end === undefined ? undefined : lt(SessionMessageTable.seq, end),
-      ),
-    )
-    .orderBy(asc(SessionMessageTable.seq))
-    .all()
-    .pipe(Effect.orDie)
-  const first = steps[0]
-  const final = steps[steps.length - 1]
-  const from = steps.find((step) => step.start)?.start
-  if (!first || !final || !from) return []
-  const switches = yield* db
-    .select({
-      seq: SessionMessageTable.seq,
-      location: sql<string>`json_extract(${SessionMessageTable.data}, '$.location')`,
-      previous: sql<string | null>`json_extract(${SessionMessageTable.data}, '$.previous.location')`,
-    })
-    .from(SessionMessageTable)
-    .where(and(eq(SessionMessageTable.session_id, sessionID), eq(SessionMessageTable.type, "location-switched")))
-    .orderBy(asc(SessionMessageTable.seq))
-    .all()
-    .pipe(Effect.orDie)
-  if (switches.some((row) => row.seq > first.seq && row.seq < final.seq))
-    return yield* new TurnRangeError({ sessionID, field: "to", message: "Turn range spans a location change" })
-  const before = switches.findLast((row) => row.seq < first.seq)?.location
-  const after = switches.find((row) => row.seq > first.seq)?.previous
-  const location = before ? decodeLocation(before) : after ? decodeLocation(after) : input.session.location
-  const recorded = steps.findLast((step) => step.end)?.end
-  return yield* Effect.gen(function* () {
-    const snapshot = yield* Snapshot.Service
-    const running = input.active && final.completed === null
-    const to = running ? ((yield* snapshot.capture()) ?? recorded) : recorded
-    if (!to) return []
-    return yield* snapshot.diff({
-      from: Snapshot.ID.make(from),
-      to: Snapshot.ID.make(to),
-      context: input.context ?? PATCH_CONTEXT_LINES,
-    })
-  }).pipe(Effect.provide(locations.get(location)))
-})

packages/core/src/session/info.ts

@@ -50,6 +50,7 @@ export function fromRow(row: typeof SessionTable.$inferSelect): SessionSchema.In
     }),
     subpath: row.path ? RelativePath.make(row.path) : undefined,
     metadata: row.metadata ?? undefined,
+    permissions: row.permission ?? undefined,
     revert: row.revert ? decodeRevert(row.revert) : undefined,
     outcome: row.idle_outcome ?? undefined,
     time: {

packages/core/src/session/message-updater.ts

@@ -60,21 +60,6 @@ export function update(adapter: Adapter, event: SessionEvent.DurableEvent) {
     )
   })
 
-  const idle = (outcome: SessionMessage.Idle["outcome"]) =>
-    clearCurrentRetry.pipe(
-      Effect.andThen(
-        adapter.appendMessage(
-          SessionMessage.Idle.make({
-            id: SessionMessage.ID.fromEvent(event.id),
-            type: "idle",
-            outcome,
-            metadata: event.metadata,
-            time: { created },
-          }),
-        ),
-      ),
-    )
-
   const project = pipe(
     Match.type<SessionEvent.DurableEvent>(),
     Match.discriminatorsExhaustive("type")({
@@ -131,6 +116,7 @@ export function update(adapter: Adapter, event: SessionEvent.DurableEvent) {
           )
         }),
       "session.renamed": () => Effect.void,
+      "session.permissions.updated": () => Effect.void,
       "session.deleted": () => Effect.void,
       "session.forked": () => Effect.void,
       "session.inbox.delivered": () => Effect.void,
@@ -138,11 +124,9 @@ export function update(adapter: Adapter, event: SessionEvent.DurableEvent) {
       "session.inbox.cancelled": () => Effect.void,
       "session.inbox.delivery.changed": () => Effect.void,
       "session.execution.started": () => Effect.void,
-      "session.execution.succeeded": () => idle("succeeded"),
-      "session.execution.failed": () => idle("failed"),
-      // Shutdown keeps the execution claim and the resumed drain continues the turn.
-      "session.execution.interrupted": (event) =>
-        event.data.reason === "shutdown" ? clearCurrentRetry : idle("interrupted"),
+      "session.execution.succeeded": () => clearCurrentRetry,
+      "session.execution.failed": () => clearCurrentRetry,
+      "session.execution.interrupted": () => clearCurrentRetry,
       "session.instructions.updated": (event) => {
         if (event.data.text === undefined) return Effect.void
         return adapter.appendMessage(

packages/core/src/session/projector.ts

@@ -160,6 +160,7 @@ const projectFork = Effect.fn("SessionProjector.projectFork")(function* (
       agent: parent.agent,
       model: parent.model,
       metadata: parent.metadata,
+      permission: parent.permission,
       version: parent.version,
       cost: 0,
       tokens_input: 0,
@@ -450,6 +451,7 @@ const layer = Layer.effectDiscard(
             agent: event.data.agent,
             model: event.data.model,
             metadata: event.data.metadata,
+            permission: event.data.permissions,
             version: event.data.version,
             time_created: event.created,
             time_updated: event.created,
@@ -571,6 +573,14 @@ const layer = Layer.effectDiscard(
         .run()
         .pipe(Effect.orDie),
     )
+    yield* bus.project(SessionEvent.PermissionsUpdated, (event) =>
+      db
+        .update(SessionTable)
+        .set({ permission: event.data.permissions, time_updated: event.created })
+        .where(eq(SessionTable.id, event.data.sessionID))
+        .run()
+        .pipe(Effect.orDie),
+    )
     yield* bus.project(SessionEvent.Viewed, (event) => {
       const idle = event.data.idle
       return db

packages/core/src/session/runner/model.ts

@@ -33,6 +33,10 @@ export const VariantUnavailableError = ModelResolver.VariantUnavailableError
 export type VariantUnavailableError = ModelResolver.VariantUnavailableError
 export const UnsupportedPackageError = ModelResolver.UnsupportedPackageError
 export type UnsupportedPackageError = ModelResolver.UnsupportedPackageError
+export const ModelConfigurationError = ModelResolver.ModelConfigurationError
+export type ModelConfigurationError = ModelResolver.ModelConfigurationError
+export const ModelInitializationError = ModelResolver.ModelInitializationError
+export type ModelInitializationError = ModelResolver.ModelInitializationError
 export const UnresolvedProviderVariablesError = ModelResolver.UnresolvedProviderVariablesError
 export type UnresolvedProviderVariablesError = ModelResolver.UnresolvedProviderVariablesError
 export const UnsupportedCompactionError = ModelResolver.UnsupportedCompactionError

packages/core/src/session/runner/to-llm-message.ts

@@ -1,4 +1,11 @@
-import { Message, ToolCallPart, ToolResultPart, type ContentPart, type ProviderMetadata } from "@opencode/ai"
+import {
+  Message,
+  ReasoningEfforts,
+  ToolCallPart,
+  ToolResultPart,
+  type ContentPart,
+  type ProviderMetadata,
+} from "@opencode/ai"
 import type { Model } from "@opencode/schema/model"
 import { Option, Schema } from "effect"
 import { fileURLToPath } from "url"
@@ -222,12 +229,31 @@ const assistant = (message: SessionMessage.Assistant, model: Model.Ref, provider
   ]
 }
 
+const EFFORT_VARIANTS = new Set<string>(ReasoningEfforts)
+
+// Budget and toggle variants reuse these names; the protocol's drift check catches ones that are not effort options.
+const variantEffort = (variant: Model.VariantID | undefined) => {
+  if (variant === undefined || variant === "default") return { effort: undefined }
+  return EFFORT_VARIANTS.has(variant) ? { effort: variant } : undefined
+}
+
+const modelSwitched = (message: SessionMessage.ModelSelected, model: Model.Ref): Message[] => {
+  const previous = message.previous
+  if (previous === undefined) return []
+  const same = (ref: Model.Ref) => ref.providerID === model.providerID && ref.id === model.id
+  if (!same(message.model) || !same(previous)) return []
+  const to = variantEffort(message.model.variant)
+  const from = variantEffort(previous.variant)
+  if (to === undefined || from === undefined) return []
+  return [Message.effort({ effort: to.effort, previous: from.effort })]
+}
+
 function toLLMMessage(message: SessionMessage.Info, model: Model.Ref, providerMetadataKey: string): Message[] {
   switch (message.type) {
     case "agent-switched":
-    case "model-switched":
-    case "idle":
       return []
+    case "model-switched":
+      return modelSwitched(message, model)
     case "location-switched":
       return [
         Message.make({

packages/core/src/session/session.ts

@@ -3,6 +3,7 @@ export * as Session from "./session.js"
 import { DateTime, Effect, Fiber, Scope } from "effect"
 import type { Agent } from "@opencode/schema/agent"
 import type { Model } from "@opencode/schema/model"
+import type { Permission } from "@opencode/schema/permission"
 import { Event } from "@opencode/schema/event"
 import { FSUtil } from "@opencode/util/fs-util"
 import { Bus } from "../bus.js"
@@ -72,6 +73,13 @@ export const make = Effect.fn("Session.make")(function* () {
     yield* get(sessionID)
     yield* bus.publish(SessionEvent.Renamed, { sessionID, title: input.title })
   })
+  const setPermissions = Effect.fn("Session.setPermissions")(function* (
+    sessionID: SessionSchema.ID,
+    input: { permissions: Permission.Ruleset },
+  ) {
+    yield* get(sessionID)
+    yield* bus.publish(SessionEvent.PermissionsUpdated, { sessionID, permissions: input.permissions })
+  })
   const switchAgent = Effect.fn("Session.switchAgent")(function* (
     sessionID: SessionSchema.ID,
     input: { agent: Agent.ID },
@@ -334,6 +342,7 @@ export const make = Effect.fn("Session.make")(function* () {
     message,
     view,
     rename,
+    setPermissions,
     switchAgent,
     switchModel,
     inbox,
@@ -356,6 +365,7 @@ export const make = Effect.fn("Session.make")(function* () {
     const message = operations.message.bind(undefined, sessionID)
     const view = operations.view.bind(undefined, sessionID)
     const rename = operations.rename.bind(undefined, sessionID)
+    const setPermissions = operations.setPermissions.bind(undefined, sessionID)
     const switchAgent = operations.switchAgent.bind(undefined, sessionID)
     const switchModel = operations.switchModel.bind(undefined, sessionID)
     const inbox = operations.inbox.bind(undefined, sessionID)
@@ -381,6 +391,7 @@ export const make = Effect.fn("Session.make")(function* () {
       message,
       view,
       rename,
+      setPermissions,
       switchAgent,
       switchModel,
       inbox,

packages/core/src/session/sql.ts

@@ -5,7 +5,7 @@ import { ProjectTable } from "../project/sql.js"
 import type { SessionMessage } from "./message.js"
 import type { SessionInbox } from "./inbox.js"
 import type { FileDiff } from "@opencode/schema/file-diff"
-import type { PermissionV1 } from "@opencode/schema/permission-v1"
+import type { Permission } from "@opencode/schema/permission"
 import type { Project } from "@opencode/schema/project"
 import type { SessionSchema } from "./schema.js"
 import type { Workspace } from "@opencode/schema/workspace"
@@ -49,7 +49,7 @@ export const SessionTable = sqliteTable(
     tokens_cache_read: integer().notNull().default(0),
     tokens_cache_write: integer().notNull().default(0),
     revert: text({ mode: "json" }).$type<Session.Revert | RevertV1>(),
-    permission: text({ mode: "json" }).$type<PermissionV1.Ruleset>(),
+    permission: text({ mode: "json" }).$type<Permission.Ruleset>(),
     agent: text(),
     model: text({ mode: "json" }).$type<{
       id: string

packages/core/src/session/to-session-error.ts

@@ -55,6 +55,8 @@ export function toSessionError(cause: unknown): SessionError.Error {
     cause instanceof SessionRunnerModel.ModelUnavailableError ||
     cause instanceof SessionRunnerModel.VariantUnavailableError ||
     cause instanceof SessionRunnerModel.UnsupportedPackageError ||
+    cause instanceof SessionRunnerModel.ModelConfigurationError ||
+    cause instanceof SessionRunnerModel.ModelInitializationError ||
     cause instanceof SessionRunnerModel.UnresolvedProviderVariablesError
   )
     return { type: "provider.no-route", message: cause.message }

packages/core/src/session/transfer.ts

@@ -103,6 +103,7 @@ const layer = Layer.effect(
               agent: input.data.info.agent,
               model: input.data.info.model,
               metadata: input.data.info.metadata,
+              permissions: input.data.info.permissions,
             },
             {
               location: input.location,

packages/core/src/snapshot.ts

@@ -131,55 +131,38 @@ const layer = Layer.effect(
       )
     })
 
-    const comparison = Effect.fnUntraced(function* (operation: "files" | "diff", input: CompareInput) {
+    const compare = Effect.fnUntraced(function* (operation: "files" | "diff", input: CompareInput) {
       const repo = yield* repository.pipe(Effect.mapError((cause) => failure(operation, cause)))
-      return {
-        source: repo.source,
+      const comparison = {
         repository: repo.snapshotRepository,
         from: Git.TreeID.make(input.from),
         to: Git.TreeID.make(input.to),
       }
-    })
-
-    // Snapshots track every scoped file; the source repository's ignore rules decide what callers see.
-    const ignored = Effect.fnUntraced(function* (
-      operation: "files" | "diff",
-      source: Git.Repository,
-      paths: readonly RelativePath[],
-    ) {
-      return yield* git.index
-        .ignored({ repository: source, paths })
+      const files = yield* git.tree.files(comparison).pipe(Effect.mapError((cause) => failure(operation, cause)))
+      const ignored = yield* git.index
+        .ignored({ repository: repo.source, paths: files })
         .pipe(Effect.mapError((cause) => failure(operation, cause)))
+      return {
+        input: comparison,
+        files,
+        ignored,
+      }
     })
 
     const files = Effect.fn("Snapshot.files")(function* (input: CompareInput) {
-      const compared = yield* comparison("files", input)
-      const changed = yield* git.tree
-        .files({ repository: compared.repository, from: compared.from, to: compared.to })
-        .pipe(Effect.mapError((cause) => failure("files", cause)))
-      const skipped = yield* ignored("files", compared.source, changed)
-      return changed.filter((file) => !skipped.has(file))
+      const comparison = yield* compare("files", input)
+      return comparison.files.filter((file) => !comparison.ignored.has(file))
     })
 
     const diff = Effect.fn("Snapshot.diff")(function* (input: DiffInput) {
-      if (input.paths?.length === 0) return []
-      const compared = yield* comparison("diff", input)
-      // Only an explicit selection becomes a pathspec; ignored paths are dropped from the result instead.
-      const diffs = yield* git.tree
+      const comparison = yield* compare("diff", input)
+      return yield* git.tree
         .diff({
-          repository: compared.repository,
-          from: compared.from,
-          to: compared.to,
+          ...comparison.input,
           context: input.context,
-          paths: input.paths,
+          paths: (input.paths ?? comparison.files).filter((file) => !comparison.ignored.has(file)),
         })
         .pipe(Effect.mapError((cause) => failure("diff", cause)))
-      const skipped = yield* ignored(
-        "diff",
-        compared.source,
-        diffs.map((file) => RelativePath.make(file.file)),
-      )
-      return diffs.filter((file) => !skipped.has(RelativePath.make(file.file)))
     })
 
     const plan = Effect.fnUntraced(function* (worktree: AbsolutePath, input: RestoreInput) {

packages/core/src/tool/mcp.ts

@@ -99,8 +99,19 @@ export const layer = Layer.effect(
                           },
                     )
                     const text = content.flatMap((part) => (part.type === "text" ? [part.text] : [])).join("\n")
+                    const output = () => {
+                      if (result.structured !== undefined) return result.structured
+                      if (text === "") return null
+                      // Agents assume JSON returned as text is already an object, so parse it when the server declares no schema.
+                      if (tool.outputSchema === undefined && (text.startsWith("{") || text.startsWith("["))) {
+                        try {
+                          return JSON.parse(text)
+                        } catch {}
+                      }
+                      return text
+                    }
                     return {
-                      output: result.structured ?? (text === "" ? null : text),
+                      output: output(),
                       ...(content.length === 0 ? {} : { content }),
                     }
                   }).pipe(

packages/core/test/git.test.ts

@@ -6,7 +6,6 @@ import { Effect } from "effect"
 import { LayerNode } from "@opencode/util/effect/layer-node"
 import { Git } from "@opencode/core/git"
 import { AbsolutePath, RelativePath } from "@opencode/core/schema"
-import { VcsPatch } from "@opencode/core/vcs/patch"
 import { branch, commit, initRepo, read, withRemote } from "./fixture/git"
 import { tmpdir } from "./fixture/tmpdir"
 import { testEffect } from "./lib/effect"
@@ -197,42 +196,6 @@ describe("Git trees", () => {
     }),
   )
 
-  it.live("caps batched tree patches, keeps per-file stats past the cap, and matches non-ASCII names", () =>
-    Effect.gen(function* () {
-      const root = yield* Effect.acquireRelease(
-        Effect.promise(() => tmpdir()),
-        (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
-      )
-      yield* Effect.promise(() => initRepo(root.path))
-      const git = yield* Git.Service
-      const repository = yield* git.repo.discover(AbsolutePath.make(root.path))
-      if (!repository) throw new Error("Repository not found")
-      const before = yield* git.tree.capture({ repository, scopes: [RelativePath.make(".")] })
-      const lines = Math.ceil(VcsPatch.MAX_TOTAL_PATCH_BYTES / 80) + 1
-      yield* Effect.promise(async () => {
-        await Bun.write(path.join(root.path, "a-small.txt"), "small\n")
-        await Bun.write(path.join(root.path, "b-large.txt"), `${"x".repeat(79)}\n`.repeat(lines))
-        await Bun.write(path.join(root.path, "c-binary.bin"), new Uint8Array([0, 1, 2, 3]))
-        await Bun.write(path.join(root.path, "a-caf\u00e9.txt"), "caf\u00e9\n")
-      })
-      const after = yield* git.tree.capture({ repository, scopes: [RelativePath.make(".")] })
-
-      const diffs = yield* git.tree.diff({ repository, from: before, to: after, context: 0 })
-      expect(diffs.map((item) => [item.file, item.status, item.additions, item.deletions])).toEqual([
-        ["a-caf\u00e9.txt", "added", 1, 0],
-        ["a-small.txt", "added", 1, 0],
-        ["b-large.txt", "added", lines, 0],
-        ["c-binary.bin", "added", 0, 0],
-      ])
-      // Patch headers are not NUL-delimited; a quoted (octal-escaped) header would orphan this chunk.
-      expect(diffs[0]?.patch).toContain("+caf\u00e9\n")
-      expect(diffs[1]?.patch).toContain("+small\n")
-      expect(diffs[2]?.patch).toBe(VcsPatch.emptyPatch("b-large.txt"))
-      expect(diffs[3]?.patch).toBe("")
-      expect(yield* git.tree.diff({ repository, from: before, to: after, paths: [] })).toEqual([])
-    }),
-  )
-
   it.live("captures, compares, previews, and restores scoped trees", () =>
     Effect.gen(function* () {
       const root = yield* Effect.acquireRelease(

packages/core/test/mcp.test.ts

@@ -324,6 +324,32 @@ const mcp = Layer.mock(Mcp.Service, {
         description: "Status",
         inputSchema: { type: "object", properties: {} },
       }),
+      new Mcp.Tool({
+        server: Mcp.ServerName.make("demo"),
+        name: "issues",
+        description: "Returns JSON as text",
+        inputSchema: { type: "object", properties: {} },
+      }),
+      new Mcp.Tool({
+        server: Mcp.ServerName.make("demo"),
+        name: "count",
+        description: "Returns a number as text",
+        inputSchema: { type: "object", properties: {} },
+      }),
+      new Mcp.Tool({
+        server: Mcp.ServerName.make("demo"),
+        name: "typed",
+        description: "Declares a string output and returns JSON as text",
+        inputSchema: { type: "object", properties: {} },
+        outputSchema: { type: "string" },
+      }),
+      new Mcp.Tool({
+        server: Mcp.ServerName.make("direct"),
+        name: "issues",
+        codemode: false,
+        description: "Returns JSON as text",
+        inputSchema: { type: "object", properties: {} },
+      }),
       new Mcp.Tool({
         server: Mcp.ServerName.make("direct"),
         name: "lookup",
@@ -374,6 +400,20 @@ const mcp = Layer.mock(Mcp.Service, {
           isError: false,
           content: [{ type: "text", text: "hello" }],
         })
+      if (input.name === "issues" || input.name === "typed")
+        return new Mcp.ToolResult({
+          server: Mcp.ServerName.make(input.server),
+          tool: input.name,
+          isError: false,
+          content: [{ type: "text", text: '{"issues":[{"id":1}]}' }],
+        })
+      if (input.name === "count")
+        return new Mcp.ToolResult({
+          server: Mcp.ServerName.make(input.server),
+          tool: input.name,
+          isError: false,
+          content: [{ type: "text", text: "42" }],
+        })
       return new Mcp.ToolResult({
         server: Mcp.ServerName.make(input.server),
         tool: input.name,
@@ -1943,6 +1983,7 @@ it.effect("advertises MCP output schemas to Code Mode", () =>
 
     expect(toolSet.definitions.map((tool) => tool.name)).toEqual([
       "direct_fail",
+      "direct_issues",
       "direct_lookup",
       "direct_media",
       "execute",
@@ -2033,6 +2074,39 @@ it.effect("returns content-only MCP results through Code Mode", () =>
   }),
 )
 
+it.effect("parses JSON text results from MCP tools without an output schema", () =>
+  Effect.gen(function* () {
+    assertion = yield* Deferred.make<Permission.AssertInput>()
+    decision = Effect.void
+    const registry = yield* Tool.Service
+    const registration = yield* McpTool.Service
+    yield* registration.flush
+    const toolSet = yield* registry.snapshot()
+
+    const run = (code: string) =>
+      toolSet
+        .execute({
+          sessionID: Session.ID.make("ses_mcp_json_text"),
+          ...toolIdentity,
+          call: { type: "tool-call", id: `call_${code.length}`, name: "execute", input: { code } },
+        })
+        .pipe(Effect.map((execution) => execution.output.output))
+
+    expect(yield* run("return (await tools.demo.issues({})).issues[0].id")).toBe("1")
+    expect(yield* run("return typeof (await tools.demo.count({}))")).toBe("string")
+    expect(yield* run("return typeof (await tools.demo.typed({}))")).toBe("string")
+
+    // Outside Code Mode the content the model reads is the original text.
+    expect(
+      yield* toolSet.execute({
+        sessionID: Session.ID.make("ses_mcp_json_text"),
+        ...toolIdentity,
+        call: { type: "tool-call", id: "call_direct_issues", name: "direct_issues", input: {} },
+      }),
+    ).toMatchObject({ output: { issues: [{ id: 1 }] }, content: [{ type: "text", text: '{"issues":[{"id":1}]}' }] })
+  }),
+)
+
 it.effect("advertises MCP tools directly when Code Mode is disabled for the server", () =>
   Effect.gen(function* () {
     const registry = yield* Tool.Service

packages/core/test/model-resolver.test.ts

@@ -1395,6 +1395,81 @@ describe("ModelResolver", () => {
     }),
   )
 
+  it.effect("reports provider configuration errors from supported packages", () =>
+    Effect.gen(function* () {
+      const failure = yield* ModelResolver.fromCatalogModel(
+        model(Provider.aisdk("@ai-sdk/azure"), {
+          providerID: Provider.ID.azure,
+          modelID: "gpt-5.4-nano",
+        }),
+        Credential.OAuth.make({
+          type: "oauth",
+          methodID: Integration.MethodID.make("oauth"),
+          access: "oauth-token",
+          refresh: "refresh",
+          expires: Date.now() + 60_000,
+        }),
+      ).pipe(Effect.flip)
+
+      expect(failure).toMatchObject({
+        _tag: "SessionRunnerModel.ModelConfigurationError",
+        providerID: "azure",
+        modelID: "test-model",
+        package: "aisdk:@ai-sdk/azure",
+        detail: "Azure requires resourceName or baseURL",
+      })
+      expect(failure.message).toBe("Cannot initialize azure/test-model: Azure requires resourceName or baseURL")
+    }),
+  )
+
+  it.effect("distinguishes unexpected constructor failures from configuration errors", () =>
+    Effect.gen(function* () {
+      const failure = yield* ModelResolver.fromCatalogModel(model("@opencode/ai/providers/custom"), undefined, {
+        loadPackage: () =>
+          Effect.succeed({
+            model: () => {
+              throw new Error("custom provider crashed")
+            },
+          }),
+      }).pipe(Effect.flip)
+
+      expect(failure).toMatchObject({
+        _tag: "SessionRunnerModel.ModelInitializationError",
+        phase: "construct",
+        detail: "custom provider crashed",
+      })
+    }),
+  )
+
+  it.effect("reports package load and AISDK initialization failures with their causes", () =>
+    Effect.gen(function* () {
+      const load = yield* ModelResolver.fromCatalogModel(model("@opencode/ai/providers/custom"), undefined, {
+        loadPackage: (specifier) =>
+          Effect.fail(
+            new Provider.LoadError({ package: specifier, cause: new Error(`Provider package ${specifier} is broken`) }),
+          ),
+      }).pipe(Effect.flip)
+      expect(load).toMatchObject({
+        _tag: "SessionRunnerModel.ModelInitializationError",
+        phase: "load",
+        detail: "Provider package @opencode/ai/providers/custom is broken",
+      })
+
+      const init = yield* ModelResolver.fromCatalogModel(model(Provider.aisdk("@ai-sdk/cohere")), undefined, {
+        loadAISDK: (runtime) =>
+          Effect.fail(
+            new AISDK.InitError({ providerID: runtime.providerID, cause: new Error("Cohere plugin failed") }),
+          ),
+      }).pipe(Effect.flip)
+      expect(init).toMatchObject({
+        _tag: "SessionRunnerModel.ModelInitializationError",
+        phase: "init",
+        detail: "Cohere plugin failed",
+      })
+      expect(init.message).toBe("Cannot initialize test-provider/test-model: Cohere plugin failed")
+    }),
+  )
+
   it.effect("drops an empty API key before loading an AISDK package", () =>
     Effect.gen(function* () {
       const native = yield* ModelResolver.fromCatalogModel(

packages/core/test/permission.test.ts

@@ -224,6 +224,34 @@ describe("Permission", () => {
     }),
   )
 
+  it.effect("merges session rules after agent rules and before saved approvals", () =>
+    Effect.gen(function* () {
+      yield* setup([{ action: "*", resource: "*", effect: "allow" }])
+      const { db } = yield* Database.Service
+      const service = yield* Permission.Service
+      const setSession = (permission: Permission.Ruleset) =>
+        db
+          .update(SessionTable)
+          .set({ permission })
+          .where(eq(SessionTable.id, Session.ID.make("ses_test")))
+          .run()
+          .pipe(Effect.orDie)
+
+      yield* setSession([{ action: "edit", resource: "/original/**", effect: "deny" }])
+      expect(yield* service.ask(assertion({ action: "edit", resources: ["/original/src/index.ts"] }))).toMatchObject({
+        effect: "deny",
+      })
+
+      yield* setRules([])
+      const saved = yield* PermissionSaved.Service
+      yield* saved.add({ projectID: Project.ID.global, action: "bash", resources: ["pwd"] })
+      yield* setSession([{ action: "bash", resource: "*", effect: "deny" }])
+      expect(yield* service.ask(assertion({ action: "bash", resources: ["pwd"] }))).toMatchObject({ effect: "deny" })
+      yield* setSession([{ action: "bash", resource: "*", effect: "ask" }])
+      expect(yield* service.ask(assertion({ action: "bash", resources: ["pwd"] }))).toMatchObject({ effect: "allow" })
+    }),
+  )
+
   it.effect("uses saved bash approvals while preserving configured deny precedence", () =>
     Effect.gen(function* () {
       yield* setup()

packages/core/test/plugin/host.ts

@@ -108,6 +108,7 @@ export function host(overrides: Overrides = {}): Plugin.Context {
       list: () => Effect.die("unused permission.list"),
       get: () => Effect.die("unused permission.get"),
       reply: () => Effect.die("unused permission.reply"),
+      rules: () => Effect.die("unused permission.rules"),
     },
     plugin: overrides.plugin ?? {
       list: () => Effect.die("unused plugin.list"),

packages/core/test/plugin/optimize.test.ts

@@ -19,9 +19,11 @@ import PROMPT_GPT from "../../src/plugin/system-prompt/gpt.txt"
 import PROMPT_ASTRA from "../../src/plugin/system-prompt/gpt-astra.txt"
 import PROMPT_KIMI from "../../src/plugin/system-prompt/kimi.txt"
 import PROMPT_TRINITY from "../../src/plugin/system-prompt/trinity.txt"
+import PROMPT_ANTHROPIC from "../../src/plugin/system-prompt/anthropic.txt"
 
 const it = testEffect(PluginTestLayer)
 const fallback = SessionSystemPrompt.make([])
+const appended = `${fallback}\n\n${SessionSystemPrompt.render(PROMPT_ANTHROPIC, [])}`
 const makeHost = Effect.gen(function* () {
   const agents = yield* Agent.Service
   const plugins = yield* Plugin.Service
@@ -48,6 +50,7 @@ describe("OptimizePlugin", () => {
   test("enables prompt plugins without model-specific tool optimization", () => {
     expect(OptimizePlugin.Plugins.map((plugin) => plugin.id)).toEqual([
       "opencode.prompt.openai",
+      "opencode.prompt.anthropic",
       "opencode.prompt.kimi",
       "opencode.prompt.arcee",
       "opencode.prompt.meta",
@@ -76,7 +79,7 @@ describe("OptimizePlugin", () => {
         ["gpt-5-codex", PROMPT_GPT],
         ["gpt-6-astra", PROMPT_ASTRA],
         ["gemini-2.5-pro", fallback],
-        ["claude-sonnet-4", fallback],
+        ["claude-sonnet-4", appended],
         ["kimi-k2", PROMPT_KIMI],
         ["trinity", PROMPT_TRINITY],
         ["meta/muse-spark-1.1", PROMPT_META.replaceAll("{{MODEL_NAME}}", "Muse Spark")],
@@ -128,6 +131,30 @@ describe("OptimizePlugin", () => {
     }),
   )
 
+  it.effect("appends the Anthropic prompt to the baseline without changing tools or project instructions", () =>
+    Effect.gen(function* () {
+      const catalog = yield* Catalog.Service
+      const hooks = yield* PluginHooks.Service
+      const pluginHost = yield* makeHost
+      yield* catalog.transform((editor) =>
+        editor.model.update(Provider.ID.make("test"), Model.ID.make("claude-sonnet-4"), () => {}),
+      )
+      yield* OptimizePlugin.AnthropicPlugin.effect(pluginHost)
+      const event = context("claude-sonnet-4")
+      event.system.push(SystemPart.make("Project instructions"))
+
+      yield* hooks.trigger("session", "context", event)
+
+      const baseline = SessionSystemPrompt.render(fallback, Object.keys(event.tools))
+      expect(event.system.map((part) => part.text)).toEqual([
+        `${baseline}\n\n${SessionSystemPrompt.render(PROMPT_ANTHROPIC, Object.keys(event.tools))}`,
+        "Project instructions",
+      ])
+      expect(event.system[0]?.text.startsWith(baseline)).toBe(true)
+      expect(Object.keys(event.tools).sort()).toEqual(["edit", "glob", "grep", "patch", "read", "shell", "write"])
+    }),
+  )
+
   it.effect("curates search tools across providers without changing editing tools", () =>
     Effect.gen(function* () {
       const hooks = yield* PluginHooks.Service
@@ -298,7 +325,7 @@ describe("OptimizePlugin", () => {
         ["codex-family-alias", "custom-deployment", "GPT-CODEX", fallback],
         ["astra-api-alias", "gpt-6-astra", undefined, fallback],
         ["astra-family-alias", "custom-deployment", "gpt-6", fallback],
-        ["claude-catalog-alias", "custom-model", undefined, fallback],
+        ["claude-catalog-alias", "custom-model", undefined, appended],
         ["anthropic-api-alias", "Claude-Opus-4-8", undefined, fallback],
         ["anthropic-family-alias", "custom-deployment", "CLAUDE-SONNET", fallback],
       ] as const

packages/core/test/plugin/provider-xai.test.ts

@@ -69,7 +69,7 @@ describe("XAIPlugin", () => {
     }),
   )
 
-  it.effect("keeps xAI Responses WebSockets opt-in", () =>
+  it.effect("enables xAI Responses WebSockets", () =>
     Effect.gen(function* () {
       const catalog = yield* Catalog.Service
       const providerID = Provider.ID.make("xai")
@@ -84,7 +84,7 @@ describe("XAIPlugin", () => {
 
       const model = yield* catalog.model.get(providerID, Model.ID.make("grok-4.6"))
       expect(model?.capabilities.responsesWebsockets).toBe(true)
-      expect(model?.websocket).toBeUndefined()
+      expect(model?.websocket).toBe(true)
     }),
   )
 })

packages/core/test/session-create.test.ts

@@ -388,6 +388,32 @@ describe("Session.create", () => {
     }),
   )
 
+  it.effect("stores permission rules, inherits them through children and forks, and replaces them", () =>
+    Effect.gen(function* () {
+      const session = yield* Session.Service
+      const bus = yield* Bus.Service
+      const { db } = yield* Database.Service
+      const permissions = [{ action: "edit", resource: "/original/**", effect: "deny" as const }]
+
+      const created = yield* session.create({ location, permissions })
+      expect(created.permissions).toEqual(permissions)
+      expect((yield* session.create({ parentID: created.id })).permissions).toEqual(permissions)
+      expect((yield* session.create({ parentID: created.id, permissions: [] })).permissions).toEqual([])
+
+      yield* session.prompt({ sessionID: created.id, text: "Fork context", resume: false })
+      yield* SessionInbox.promote(db, bus, created.id, "steer")
+      const forked = yield* session.fork({ sessionID: created.id, boundary: { type: "through" } })
+      expect(forked.permissions).toEqual(permissions)
+
+      const replaced = [{ action: "shell", resource: "*", effect: "ask" as const }]
+      yield* session.setPermissions({ sessionID: created.id, permissions: replaced })
+      expect((yield* session.get(created.id)).permissions).toEqual(replaced)
+      expect(
+        yield* session.setPermissions({ sessionID: Session.ID.create(), permissions: replaced }).pipe(Effect.flip),
+      ).toBeInstanceOf(Session.NotFoundError)
+    }),
+  )
+
   it.effect("inherits location from an existing parent when omitted", () =>
     Effect.gen(function* () {
       const session = yield* Session.Service
@@ -1330,7 +1356,12 @@ describe("SessionTransfer", () => {
       const transfer = yield* SessionTransfer.Service
       const bus = yield* Bus.Service
       const { db } = yield* Database.Service
-      const template = yield* session.create({ location, title: "Exported", metadata: { channel: "C123" } })
+      const template = yield* session.create({
+        location,
+        title: "Exported",
+        metadata: { channel: "C123" },
+        permissions: [{ action: "edit", resource: "*", effect: "deny" }],
+      })
       const sessionID = Session.ID.create()
       const sourceMessageID = SessionMessage.ID.create()
       const errorMessageID = SessionMessage.ID.create()
@@ -1376,7 +1407,13 @@ describe("SessionTransfer", () => {
       })
       const messages = yield* session.messages({ sessionID, order: "asc" })
 
-      expect(imported).toMatchObject({ id: sessionID, title: "Exported", location, metadata: { channel: "C123" } })
+      expect(imported).toMatchObject({
+        id: sessionID,
+        title: "Exported",
+        location,
+        metadata: { channel: "C123" },
+        permissions: [{ action: "edit", resource: "*", effect: "deny" }],
+      })
       expect(imported.time).toMatchObject({
         updated: DateTime.makeUnsafe(1_000),
         idle: DateTime.makeUnsafe(200),

packages/core/test/session-diff.test.ts

@@ -1,198 +0,0 @@
-import { $ } from "bun"
-import { describe, expect } from "bun:test"
-import fs from "fs/promises"
-import path from "path"
-import { Effect } from "effect"
-import { Agent } from "@opencode/core/agent"
-import { Bus } from "@opencode/core/bus"
-import { Database } from "@opencode/core/database/database"
-import { AppNodeBuilder } from "@opencode/core/effect/app-node-builder"
-import { LocationServiceMap } from "@opencode/core/location-service-map"
-import { Model } from "@opencode/core/model"
-import { Plugin } from "@opencode/core/plugin"
-import { Provider } from "@opencode/core/provider"
-import { AbsolutePath } from "@opencode/core/schema"
-import { Session } from "@opencode/core/session"
-import { SessionDiff } from "@opencode/core/session/diff"
-import { SessionEvent } from "@opencode/core/session/event"
-import { SessionExecution } from "@opencode/core/session/execution"
-import { SessionInbox } from "@opencode/core/session/inbox"
-import { SessionMessage } from "@opencode/core/session/message"
-import { SessionProjector } from "@opencode/core/session/projector"
-import { Snapshot } from "@opencode/core/snapshot"
-import { Money } from "@opencode/schema/money"
-import { LayerNode } from "@opencode/util/effect/layer-node"
-import { Global } from "@opencode/util/global"
-import { tempGlobalLayer } from "./fixture/global"
-import { offlineModels } from "./fixture/models"
-import { tmpdirScoped } from "./fixture/tmpdir"
-import { testEffect } from "./lib/effect"
-
-const it = testEffect(
-  AppNodeBuilder.build(
-    LayerNode.group([Database.node, Bus.node, SessionProjector.node, Session.node, LocationServiceMap.node]),
-    [Global.node.replace(tempGlobalLayer), SessionExecution.node.replace(SessionExecution.noopLayer), offlineModels],
-  ),
-)
-
-const summarize = (file: { file: string; status: string; additions: number; deletions: number }) => [
-  file.file,
-  file.status,
-  file.additions,
-  file.deletions,
-]
-
-describe("Session.diff", () => {
-  it.live(
-    "diffs the busy period containing a user message and ranges across later turns",
-    () =>
-      Effect.gen(function* () {
-        const tmp = yield* tmpdirScoped()
-        const directory = path.join(tmp.path, "project")
-        const write = (name: string, content: string) => () => Bun.write(path.join(directory, name), content)
-        yield* Effect.promise(async () => {
-          await fs.mkdir(directory)
-          await write("first.txt", "first\n")()
-          await write("second.txt", "second\n")()
-          await write("manual.txt", "manual\n")()
-          await $`git init -q`.cwd(directory).quiet()
-          await $`git -c core.fsmonitor=false add .`.cwd(directory).quiet()
-        })
-        const sessions = yield* Session.Service
-        const database = yield* Database.Service
-        const bus = yield* Bus.Service
-        const locations = yield* LocationServiceMap.Service
-        const created = yield* sessions.create({ location: { directory: AbsolutePath.make(directory) } })
-        const diff = (input?: { messageID?: SessionMessage.ID; to?: SessionMessage.ID }) =>
-          sessions
-            .diff({ sessionID: created.id, context: 0, ...input })
-            .pipe(Effect.map((files) => files.map(summarize)))
-        expect(yield* diff()).toEqual([])
-
-        yield* Effect.gen(function* () {
-          const plugins = yield* Plugin.Service
-          yield* plugins.awaitActivation
-          const snapshot = yield* Snapshot.Service
-          const usage = {
-            cost: Money.USD.zero,
-            tokens: { input: 0, output: 0, reasoning: 0, cache: { read: 0, write: 0 } },
-          }
-          const prompt = Effect.fn(function* (text: string) {
-            const admitted = yield* sessions.prompt({ sessionID: created.id, text, resume: false })
-            yield* SessionInbox.promote(database.db, bus, created.id, "steer")
-            return admitted.id
-          })
-          const step = Effect.fn(function* (edit: () => Promise<unknown>, end: "recorded" | "unrecorded" | "running") {
-            const before = yield* snapshot.capture()
-            if (!before) throw new Error("Start snapshot missing")
-            const assistantMessageID = SessionMessage.ID.create()
-            yield* bus.publish(SessionEvent.Step.Started, {
-              sessionID: created.id,
-              assistantMessageID,
-              agent: Agent.defaultID,
-              model: { id: Model.ID.make("test-model"), providerID: Provider.ID.make("test-provider") },
-              snapshot: before,
-            })
-            yield* Effect.promise(edit)
-            if (end === "running") return assistantMessageID
-            const after = end === "recorded" ? yield* snapshot.capture() : undefined
-            yield* bus.publish(SessionEvent.Step.Ended, {
-              sessionID: created.id,
-              assistantMessageID,
-              finish: "stop",
-              ...usage,
-              snapshot: after,
-              files: after && before ? yield* snapshot.files({ from: before, to: after }) : undefined,
-            })
-            return assistantMessageID
-          })
-
-          const idle = (outcome: "succeeded" | "failed") =>
-            outcome === "succeeded"
-              ? bus.publish(SessionEvent.Execution.Succeeded, { sessionID: created.id })
-              : bus.publish(SessionEvent.Execution.Failed, {
-                  sessionID: created.id,
-                  error: { type: "unknown", message: "failed" },
-                })
-
-          // Before any idle marker exists, a prompt's turn ends at the next prompt.
-          const first = yield* prompt("Edit the first file")
-          const firstStep = yield* step(write("first.txt", "first edited\n"), "recorded")
-          // Edits made while idle are not a turn's work, but a range spanning them still sees them.
-          yield* Effect.promise(write("manual.txt", "manual edited\n"))
-          const second = yield* prompt("Edit the second file")
-          yield* step(write("second.txt", "second edited\n"), "recorded")
-          expect(yield* diff()).toEqual([["second.txt", "modified", 1, 1]])
-          expect(yield* diff({ messageID: first })).toEqual([["first.txt", "modified", 1, 1]])
-
-          // Once markers exist, a turn spans a whole busy period, steers included; earlier history merges into the first one.
-          yield* idle("succeeded")
-          const third = yield* prompt("Add a third file")
-          yield* step(write("third.txt", "third\n"), "recorded")
-          const steer = yield* prompt("Also add a fourth file")
-          yield* step(write("fourth.txt", "fourth\n"), "recorded")
-          yield* idle("failed")
-          const busy = [
-            ["fourth.txt", "added", 1, 0],
-            ["third.txt", "added", 1, 0],
-          ]
-          expect(yield* diff()).toEqual(busy)
-          expect(yield* diff({ messageID: steer })).toEqual(busy)
-          expect(yield* diff({ messageID: second })).toEqual([
-            ["first.txt", "modified", 1, 1],
-            ["manual.txt", "modified", 1, 1],
-            ["second.txt", "modified", 1, 1],
-          ])
-          expect(yield* diff({ messageID: first, to: third })).toEqual([
-            ["first.txt", "modified", 1, 1],
-            ["fourth.txt", "added", 1, 0],
-            ["manual.txt", "modified", 1, 1],
-            ["second.txt", "modified", 1, 1],
-            ["third.txt", "added", 1, 0],
-          ])
-          const full = yield* sessions.diff({ sessionID: created.id, messageID: first })
-          expect(full[0]?.patch).toContain("-first\n+first edited\n")
-          expect(yield* diff({ messageID: steer, to: second }).pipe(Effect.flip)).toMatchObject({
-            _tag: "Session.TurnRangeError",
-            field: "to",
-          })
-          expect(yield* diff({ messageID: firstStep }).pipe(Effect.flip)).toMatchObject({
-            _tag: "Session.TurnRangeError",
-            field: "messageID",
-          })
-          expect(yield* diff({ messageID: SessionMessage.ID.create() }).pipe(Effect.flip)).toMatchObject({
-            _tag: "Session.MessageNotFoundError",
-          })
-
-          // A completed step without an end snapshot falls back to the last recorded end.
-          yield* prompt("Edit both files again")
-          yield* step(write("first.txt", "first edited twice\n"), "recorded")
-          yield* step(write("second.txt", "second edited twice\n"), "unrecorded")
-          yield* idle("succeeded")
-          expect(yield* diff()).toEqual([["first.txt", "modified", 1, 1]])
-
-          // Only a step still running in the active session compares against the working copy.
-          yield* prompt("Delete the manual file")
-          yield* step(() => fs.rm(path.join(directory, "manual.txt")), "running")
-          expect(yield* diff()).toEqual([])
-          const session = yield* sessions.get(created.id)
-          const live = yield* SessionDiff.turn(database.db, locations, { session, active: true, context: 0 })
-          expect(live.map(summarize)).toEqual([["manual.txt", "deleted", 0, 1]])
-
-          // Reverting removes later history, markers included; a fork keeps the copied turns.
-          yield* sessions.revert.stage({ sessionID: created.id, messageID: steer, files: false })
-          yield* sessions.revert.commit(created.id)
-          expect(yield* diff()).toEqual([["third.txt", "added", 1, 0]])
-          expect(yield* diff({ messageID: steer }).pipe(Effect.flip)).toMatchObject({
-            _tag: "Session.MessageNotFoundError",
-          })
-          const forked = yield* sessions.fork({ sessionID: created.id, boundary: { type: "through" } })
-          expect((yield* sessions.diff({ sessionID: forked.id, context: 0 })).map(summarize)).toEqual([
-            ["third.txt", "added", 1, 0],
-          ])
-        }).pipe(Effect.provide(LocationServiceMap.Service.get(created.location)))
-      }),
-    // Real Location/plugin startup and Git snapshots can exceed five seconds under CI load.
-    { timeout: 30_000 },
-  )
-})

packages/core/test/session-error.test.ts

@@ -140,6 +140,30 @@ describe("toSessionError", () => {
     })
   })
 
+  test("preserves provider configuration and initialization errors", () => {
+    const configuration = new ModelResolver.ModelConfigurationError({
+      providerID: Provider.ID.make("azure"),
+      modelID: ID.make("gpt-5.4-nano"),
+      package: "aisdk:@ai-sdk/azure",
+      detail: "Azure requires resourceName or baseURL",
+    })
+    expect(toSessionError(configuration)).toEqual({
+      type: "provider.no-route",
+      message: "Cannot initialize azure/gpt-5.4-nano: Azure requires resourceName or baseURL",
+    })
+    const initialization = new ModelResolver.ModelInitializationError({
+      providerID: Provider.ID.make("custom"),
+      modelID: ID.make("model"),
+      package: "@opencode/ai/providers/custom",
+      phase: "load",
+      detail: "Provider package @opencode/ai/providers/custom is broken",
+    })
+    expect(toSessionError(initialization)).toEqual({
+      type: "provider.no-route",
+      message: "Cannot initialize custom/model: Provider package @opencode/ai/providers/custom is broken",
+    })
+  })
+
   test("retries rate limits, provider-internal, transport, and unrecognized failures", () => {
     const eligible = [
       llm(new RateLimitError({ message: "rate" })),

packages/core/test/session-execution.test.ts

@@ -561,9 +561,7 @@ describe("SessionRestart background recovery", () => {
         expect(yield* restarted.pendingBackground).toEqual([])
         expect(yield* SessionInbox.list(database.db, sessionID)).toHaveLength(delivered ? 0 : 1)
         yield* SessionInbox.promote(database.db, bus, sessionID, "steer")
-        // Recovery ends a busy period, so an idle marker follows the notification.
-        const messages = (yield* sessions.messages({ sessionID })).filter((message) => message.type !== "idle")
-        expect(messages).toMatchObject([
+        expect(yield* sessions.messages({ sessionID })).toMatchObject([
           {
             id: background.notificationID,
             type: "synthetic",
@@ -571,6 +569,7 @@ describe("SessionRestart background recovery", () => {
             metadata: { state: "completed" },
           },
         ])
+        expect(yield* sessions.messages({ sessionID })).toHaveLength(1)
       }),
     )
   }