fix(app): omit notices from Used summary (#47245 )

Co-authored-by: Brendonovich <14191578+Brendonovich@users.noreply.github.com> Co-authored-by: Brendan Allan <git@brendonovich.dev>
refactor(app): make session composer ownership explicit (#47254 )
2026-09-04 16:06:23 +00:00 · 2026-09-04 09:13:00 +00:00 · 2026-09-04 09:07:47 +00:00 · 2026-09-04 16:45:42 +08:00 · 2026-09-04 08:07:24 +00:00 · 2026-09-04 15:12:54 +08:00
66 changed files with 1252 additions and 212 deletions
@@ -11,7 +11,7 @@
 // Manual `cache: CacheHint` placements on individual parts are preserved and
 // 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 } from "./schema/messages.js"
+import { LLMRequest, Message, ToolDefinition, type ContentPart, type ToolEntry } from "./schema/messages.js"

 const AUTO: CachePolicyObject = {
  tools: true,
@@ -50,18 +50,24 @@ interface Budget {
  remaining: number
 }

-const markLastTool = (
-  tools: ReadonlyArray<ToolDefinition>,
-  hint: CacheHint,
-  budget: Budget,
-): ReadonlyArray<ToolDefinition> => {
-  if (tools.length === 0) return tools
-  const last = tools.length - 1
-  if (tools[last]!.cache || budget.remaining === 0) return tools
+const markLastTool = (tools: ReadonlyArray<ToolEntry>, hint: CacheHint, budget: Budget): ReadonlyArray<ToolEntry> => {
+  const target = tools.at(-1)
+  if (target === undefined) return tools
+  if (target.type === "namespace") {
+    const nested = markLastTool(target.tools, hint, budget)
+    return nested === target.tools ? tools : [...tools.slice(0, -1), { ...target, tools: nested }]
+  }
+  if (target.cache || budget.remaining === 0) return tools
  budget.remaining -= 1
-  return tools.map((tool, i) => (i === last ? new ToolDefinition({ ...tool, cache: hint }) : tool))
+  return [...tools.slice(0, -1), new ToolDefinition({ ...target, cache: hint })]
 }

+const countToolHints = (tools: ReadonlyArray<ToolEntry>): number =>
+  tools.reduce(
+    (count, tool) => count + (tool.type === "tool" ? (tool.cache === undefined ? 0 : 1) : countToolHints(tool.tools)),
+    0,
+  )
+
 const markSystemBoundaries = (system: LLMRequest["system"], hint: CacheHint, budget: Budget): LLMRequest["system"] => {
  if (system.length === 0) return system
  let changed = false
@@ -122,7 +128,7 @@ const markMessages = (
 }

 const countHints = (request: LLMRequest) =>
-  request.tools.reduce((count, tool) => count + (tool.cache === undefined ? 0 : 1), 0) +
+  countToolHints(request.tools) +
  request.system.reduce((count, part) => count + (part.cache === undefined ? 0 : 1), 0) +
  request.messages.reduce(
    (count, message) =>
@@ -12,9 +12,10 @@ import {
  LanguageModel,
  SystemPart,
  ToolChoice,
-  ToolDefinition,
+  ToolEntry,
  type ContentPart,
  type LanguageModelProviderOptions,
+  type ToolEntryInput,
 } from "./schema/index.js"
 import { make as makeTool, toDefinitions, type ToolSchema } from "./tool.js"

@@ -27,7 +28,7 @@ export type RequestInput<SelectedLanguageModel extends LanguageModel = LanguageM
  readonly system?: string | SystemPart | ReadonlyArray<SystemPart>
  readonly prompt?: string | ContentPart | ReadonlyArray<ContentPart>
  readonly messages?: ReadonlyArray<Message | Message.Input>
-  readonly tools?: ReadonlyArray<ToolDefinition.Input>
+  readonly tools?: ReadonlyArray<ToolEntryInput>
  readonly toolChoice?: ToolChoice.Input
  readonly generation?: GenerationOptions.Input
  readonly providerOptions?: NoInfer<LanguageModelProviderOptions<SelectedLanguageModel>>
@@ -56,7 +57,7 @@ export const request = <const SelectedLanguageModel extends LanguageModel>(
    ...rest,
    system: SystemPart.content(requestSystem),
    messages: [...(messages?.map(Message.make) ?? []), ...(prompt === undefined ? [] : [Message.user(prompt)])],
-    tools: tools?.map(ToolDefinition.make) ?? [],
+    tools: tools?.map(ToolEntry.make) ?? [],
    toolChoice: requestToolChoice ? ToolChoice.make(requestToolChoice) : undefined,
    generation: requestGeneration === undefined ? undefined : GenerationOptions.make(requestGeneration),
    providerOptions: requestProviderOptions,
@@ -1067,10 +1067,11 @@ const fromRequest = Effect.fn("AnthropicMessages.fromRequest")(function* (reques
  // 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 tools =
-    request.tools.length === 0
+    flattened.tools.length === 0
      ? undefined
-      : request.tools.map((tool) =>
+      : flattened.tools.map((tool) =>
          lowerTool(
            breakpoints,
            tool,
@@ -1088,7 +1089,7 @@ const fromRequest = Effect.fn("AnthropicMessages.fromRequest")(function* (reques
          text: part.text,
          cache_control: cacheControl(breakpoints, part.cache),
        }))
-  const messages = yield* lowerMessages(request, breakpoints)
+  const messages = yield* lowerMessages(flattened.request, breakpoints)
  if (breakpoints.dropped > 0) {
    yield* Effect.logWarning(
      `Anthropic Messages: dropped ${breakpoints.dropped} cache breakpoint(s); the API allows at most ${ANTHROPIC_BREAKPOINT_CAP} per request.`,
@@ -415,7 +415,10 @@ const lowerMessages = Effect.fn("BedrockConverse.lowerMessages")(function* (

 // System prompts share the cache-point convention: emit the text block, then
 // optionally a positional `cachePoint` marker.
-const lowerSystem = (breakpoints: BedrockCache.Breakpoints, system: ReadonlyArray<LLMRequest["system"][number]>) => {
+const lowerSystem = (
+  breakpoints: BedrockCache.Breakpoints,
+  system: ReadonlyArray<LLMRequest["system"][number]>,
+) => {
  const content = system
    .filter((part) => part.text.length > 0)
    .flatMap((part) => textWithCache(breakpoints, part.text, part.cache))
@@ -424,21 +427,22 @@ const lowerSystem = (breakpoints: BedrockCache.Breakpoints, system: ReadonlyArra

 const fromRequest = Effect.fn("BedrockConverse.fromRequest")(function* (request: LLMRequest) {
  const toolChoice = request.toolChoice ? yield* lowerToolChoice(request.toolChoice) : undefined
+  const flattened = ProviderShared.flattenToolRequest(request)
  const generation = request.generation
  // Bedrock-Claude shares Anthropic's 4-breakpoint cap. Spend the budget in
  // tools → system → messages order to favour the highest-impact prefixes.
  const breakpoints = BedrockCache.breakpoints()
  const toolConfig = (() => {
-    if (request.tools.length === 0) return undefined
+    if (flattened.tools.length === 0) return undefined
    return {
-      tools: lowerTools(request.model.compatibility?.toolSchema, breakpoints, request.tools),
+      tools: lowerTools(request.model.compatibility?.toolSchema, breakpoints, flattened.tools),
      // Converse has no native "none". Keep definitions stable for prompt
      // caching and omit only the unsupported choice.
      toolChoice,
    }
  })()
  const system = lowerSystem(breakpoints, request.system)
-  const messages = yield* lowerMessages(request, breakpoints)
+  const messages = yield* lowerMessages(flattened.request, breakpoints)
  if (breakpoints.dropped > 0) {
    yield* Effect.logWarning(
      `Bedrock Converse: dropped ${breakpoints.dropped} cache breakpoint(s); the API allows at most ${BedrockCache.BEDROCK_BREAKPOINT_CAP} per request.`,
@@ -465,7 +465,8 @@ function mapSafetySettings(value: unknown) {
 }

 const fromRequest = Effect.fn("Gemini.fromRequest")(function* (request: LLMRequest) {
-  const hasTools = request.tools.length > 0
+  const flattened = ProviderShared.flattenToolRequest(request)
+  const hasTools = flattened.tools.length > 0
  const generation = request.generation
  const options = resolveOptions(request)
  const toolSchemaCompatibility = request.model.compatibility?.toolSchema
@@ -483,7 +484,7 @@ const fromRequest = Effect.fn("Gemini.fromRequest")(function* (request: LLMReque

  return {
    cachedContent: options.cachedContent,
-    contents: yield* lowerMessages(request),
+    contents: yield* lowerMessages(flattened.request),
    safetySettings: options.safetySettings,
    serviceTier: options.serviceTier,
    systemInstruction:
@@ -491,7 +492,7 @@ const fromRequest = Effect.fn("Gemini.fromRequest")(function* (request: LLMReque
    tools: hasTools
      ? [
          {
-            functionDeclarations: request.tools.map((tool) =>
+            functionDeclarations: flattened.tools.map((tool) =>
              lowerTool(tool, ToolSchemaProjection.modelCompatibility(tool.inputSchema, toolSchemaCompatibility)),
            ),
          },
@@ -414,10 +414,11 @@ export const fromRequest = Effect.fn("MistralChat.fromRequest")(function* (reque
        tool: (name) => ({ type: "function" as const, function: { name } }),
      })
    : undefined
+  const flattened = ProviderShared.flattenToolRequest(request)
  return {
    model: request.model.id,
-    messages: yield* lowerMessages(request),
-    tools: request.tools.length > 0 ? request.tools.map(lowerTool) : undefined,
+    messages: yield* lowerMessages(flattened.request),
+    tools: flattened.tools.length > 0 ? flattened.tools.map(lowerTool) : undefined,
    tool_choice: toolChoice,
    stream: true as const,
    max_tokens: request.generation?.maxTokens,
@@ -189,6 +189,7 @@ export const InputItem = Schema.Union([
    id: Schema.optionalKey(Schema.String),
    call_id: Schema.String,
    name: Schema.String,
+    namespace: Schema.optional(Schema.String),
    arguments: Schema.String,
  }),
  Schema.Struct({
@@ -315,6 +316,7 @@ export const StreamItem = Schema.StructWithRest(
    id: Schema.optional(Schema.String),
    call_id: Schema.optional(Schema.String),
    name: Schema.optional(Schema.String),
+    namespace: Schema.optional(Schema.String),
    arguments: Schema.optional(Schema.String),
    encrypted_content: optionalNull(Schema.String),
  }),
@@ -488,6 +490,7 @@ const lowerToolCall = (part: ToolCallPart, providerMetadataKey: string): OpenRes
    ...(id === undefined ? {} : { id }),
    call_id: part.id,
    name: part.name,
+    namespace: part.namespace,
    arguments: ProviderShared.encodeJson(part.input),
  }
 }
@@ -807,14 +810,15 @@ export const fromRequestWithAdapter = Effect.fn("OpenResponses.fromRequestWithAd
  request: LLMRequest,
  adapter: ProviderAdapter,
 ) {
+  const projected = ProviderShared.flattenToolRequest(request)
  const toolSchemaCompatibility = request.model.compatibility?.toolSchema
  return {
-    ...(yield* lowerConversation(request, adapter)),
+    ...(yield* lowerConversation(projected.request, adapter)),
    ...lowerGeneration(request),
    tools:
-      request.tools.length === 0
+      projected.tools.length === 0
        ? undefined
-        : yield* Effect.forEach(request.tools, (tool) =>
+        : yield* Effect.forEach(projected.tools, (tool) =>
            lowerTool(
              adapter.name,
              tool,
@@ -1094,11 +1098,20 @@ const onOutputItemAdded = (state: ParserState, event: NormalizedEvent): StepResu
      tools: ToolStream.start(state.tools, item.id, {
        id: item.call_id,
        name: item.name ?? "",
+        namespace: item.namespace,
        input: item.arguments ?? "",
        providerMetadata: metadata,
      }),
    },
-    [...events, LLMEvent.toolInputStart({ id: item.call_id, name: item.name ?? "", providerMetadata: metadata })],
+    [
+      ...events,
+      LLMEvent.toolInputStart({
+        id: item.call_id,
+        name: item.name ?? "",
+        namespace: item.namespace,
+        providerMetadata: metadata,
+      }),
+    ],
  ]
 }

@@ -1217,7 +1230,12 @@ const onOutputItemDone = Effect.fn("OpenResponses.onOutputItemDone")(function* (
    const registered = state.tools[item.id] !== undefined
    const tools = registered
      ? state.tools
-      : ToolStream.start(state.tools, item.id, { id: item.call_id, name: item.name, providerMetadata: metadata })
+      : ToolStream.start(state.tools, item.id, {
+          id: item.call_id,
+          name: item.name,
+          namespace: item.namespace,
+          providerMetadata: metadata,
+        })
    const result =
      item.arguments === undefined
        ? yield* ToolStream.finish(state.id, tools, item.id)
@@ -1228,7 +1246,15 @@ const onOutputItemDone = Effect.fn("OpenResponses.onOutputItemDone")(function* (
    const resultEvents =
      registered || finished.length === 0
        ? finished
-        : [LLMEvent.toolInputStart({ id: item.call_id, name: item.name, providerMetadata: metadata }), ...finished]
+        : [
+            LLMEvent.toolInputStart({
+              id: item.call_id,
+              name: item.name,
+              namespace: item.namespace,
+              providerMetadata: metadata,
+            }),
+            ...finished,
+          ]
    const lifecycle = resultEvents.length ? Lifecycle.stepStart(state.lifecycle, events) : state.lifecycle
    events.push(...resultEvents)
    return [
@@ -736,6 +736,7 @@ export const fromRequest = Effect.fn("OpenAIChat.fromRequest")(function* (
    )
  const generation = request.generation
  const toolSchemaCompatibility = request.model.compatibility?.toolSchema
+  const flattened = ProviderShared.flattenToolRequest(request)
  const provider = String(request.model.provider)
  const baseURL = request.model.route.endpoint.baseURL
  const detectedMaxTokensField = detectMaxTokensField(provider, baseURL)
@@ -748,16 +749,16 @@ export const fromRequest = Effect.fn("OpenAIChat.fromRequest")(function* (
  const zaiToolStream =
    request.model.compatibility?.zaiToolStream ?? detectZaiToolStream(provider, baseURL, request.model.id)
  const hasHistory = hasToolHistory(request.messages)
-  const hasActiveTools = request.tools.length > 0
+  const hasActiveTools = flattened.tools.length > 0
  return {
    model: request.model.id,
-    messages: yield* lowerMessages(request, options),
+    messages: yield* lowerMessages(flattened.request, options),
    tools:
-      request.tools.length === 0
+      flattened.tools.length === 0
        ? hasHistory
          ? []
          : undefined
-        : request.tools.map((tool) =>
+        : flattened.tools.map((tool) =>
            lowerTool(
              tool,
              ToolSchemaProjection.modelCompatibility(tool.inputSchema, toolSchemaCompatibility),
@@ -5,7 +5,7 @@ import { Auth } from "../route/auth.js"
 import { Endpoint } from "../route/endpoint.js"
 import { Protocol } from "../route/protocol.js"
 import { HttpTransport } from "../route/transport/index.js"
-import type { LLMRequest, JsonSchema, ToolDefinition } from "../schema/index.js"
+import type { LLMRequest, JsonSchema, ToolDefinition, ToolEntry } from "../schema/index.js"
 import { OpenResponses } from "./open-responses.js"
 import { JsonObject, optionalArray, optionalNull, ProviderShared } from "./shared.js"
 import { OpenAIImage } from "./utils/openai-image.js"
@@ -75,7 +75,18 @@ const OpenAIResponsesHostedToolItem = Schema.Union([
  ),
 ])

-const OpenAIResponsesTools = Schema.Union([OpenResponses.Tool, OpenAIResponsesImageGenerationTool])
+const OpenAIResponsesNamespace = Schema.Struct({
+  type: Schema.tag("namespace"),
+  name: Schema.String,
+  description: Schema.String,
+  tools: Schema.Array(OpenResponses.Tool),
+})
+
+const OpenAIResponsesTools = Schema.Union([
+  OpenResponses.Tool,
+  OpenAIResponsesNamespace,
+  OpenAIResponsesImageGenerationTool,
+])

 const OpenAIResponsesToolChoice = Schema.Union([
  OpenResponses.ToolChoice,
@@ -128,13 +139,33 @@ const lowerTool = Effect.fn("OpenAIResponses.lowerTool")(function* (tool: ToolDe
  return yield* OpenResponses.lowerTool(NAME, tool, inputSchema)
 })

-const lowerToolChoice = (toolChoice: NonNullable<LLMRequest["toolChoice"]>, tools: ReadonlyArray<ToolDefinition>) =>
+// Native namespaces hold only function tools, so deeper levels flatten into
+// the leaf names the same way non-native protocols flatten the whole tree.
+const lowerToolEntry = Effect.fn("OpenAIResponses.lowerToolEntry")(function* (
+  tool: ToolEntry,
+  compatibility: Parameters<typeof ToolSchemaProjection.modelCompatibility>[1],
+) {
+  if (tool.type === "tool")
+    return yield* lowerTool(tool, ToolSchemaProjection.modelCompatibility(tool.inputSchema, compatibility))
+  // OpenAI requires a namespace description; fall back to a generic one so a
+  // missing description never blocks the request.
+  return {
+    type: "namespace" as const,
+    name: tool.name,
+    description: tool.description ?? `Tools in the ${tool.name} namespace.`,
+    tools: yield* Effect.forEach(ProviderShared.flattenTools(tool.tools), (leaf) =>
+      OpenResponses.lowerTool(NAME, leaf, ToolSchemaProjection.modelCompatibility(leaf.inputSchema, compatibility)),
+    ),
+  }
+})
+
+const lowerToolChoice = (toolChoice: NonNullable<LLMRequest["toolChoice"]>, tools: ReadonlyArray<ToolEntry>) =>
  ProviderShared.matchToolChoice(NAME, toolChoice, {
    auto: () => "auto" as const,
    none: () => "none" as const,
    required: () => "required" as const,
    tool: (name) =>
-      tools.some((tool) => tool.name === name && nativeImageTool(tool) !== undefined)
+      tools.some((tool) => tool.type === "tool" && tool.name === name && nativeImageTool(tool) !== undefined)
        ? ({ type: "image_generation" } as const)
        : { type: "function" as const, name },
  })
@@ -153,9 +184,7 @@ const fromRequest = Effect.fn("OpenAIResponses.fromRequest")(function* (request:
    tools:
      request.tools.length === 0
        ? undefined
-        : yield* Effect.forEach(request.tools, (tool) =>
-            lowerTool(tool, ToolSchemaProjection.modelCompatibility(tool.inputSchema, toolSchemaCompatibility)),
-          ),
+        : yield* Effect.forEach(request.tools, (tool) => lowerToolEntry(tool, toolSchemaCompatibility)),
    tool_choice:
      OpenResponses.allowedToolChoice(request) ??
      (request.toolChoice ? yield* lowerToolChoice(request.toolChoice, request.tools) : undefined),
@@ -9,11 +9,14 @@ import {
  UnsupportedOperationError,
  AIError,
  HttpContext,
+  LLMRequest,
+  Message,
+  ToolDefinition,
  type ContentPart,
-  type LLMRequest,
  type MediaPart,
  type ProviderID,
  type TextPart,
+  type ToolEntry,
  type ToolResultPart,
 } from "../schema/index.js"
 import { isRecord } from "../utils/record.js"
@@ -46,6 +49,7 @@ export const promptCacheKey = (request: LLMRequest): string | undefined => {
 export interface ToolAccumulator {
  readonly id: string
  readonly name: string
+  readonly namespace?: string
  readonly input: string
 }

@@ -279,6 +283,38 @@ export const unsupportedOperation = (input: {
    }),
  })

+/**
+ * Lower namespaces to flat definitions for protocols without a native
+ * namespace construct. Leaf names join their namespace path with `_` because
+ * `.` is not broadly accepted in provider tool names.
+ */
+export const flattenTools = (tools: ReadonlyArray<ToolEntry>, path: ReadonlyArray<string> = []) => {
+  const flat = tools.flatMap((tool): ReadonlyArray<ToolDefinition> => {
+    if (tool.type === "namespace") return flattenTools(tool.tools, [...path, tool.name])
+    if (path.length === 0) return [tool]
+    return [new ToolDefinition({ ...tool, name: [...path, tool.name].join("_") })]
+  })
+  return [...new Map(flat.map((tool) => [tool.name, tool])).values()]
+}
+
+export const flattenToolRequest = (request: LLMRequest) => {
+  const messages = request.messages.map((message) => {
+    const content = message.content.map((part) => {
+      if ((part.type !== "tool-call" && part.type !== "tool-result") || part.namespace === undefined) return part
+      return { ...part, name: `${part.namespace}_${part.name}`, namespace: undefined }
+    })
+    return content.every((part, index) => part === message.content[index])
+      ? message
+      : new Message({ ...message, content })
+  })
+  return {
+    tools: flattenTools(request.tools),
+    request: messages.every((message, index) => message === request.messages[index])
+      ? request
+      : LLMRequest.update(request, { messages }),
+  }
+}
+
 export const imageResponse = Effect.fn("ProviderShared.imageResponse")(function* (
  route: string,
  name: string,
@@ -55,6 +55,7 @@ const inputStart = (tool: PendingTool) =>
  LLMEvent.toolInputStart({
    id: tool.id,
    name: tool.name,
+    namespace: tool.namespace,
    providerExecuted: tool.providerExecuted ? true : undefined,
    providerMetadata: tool.providerMetadata,
  })
@@ -63,6 +64,7 @@ const inputDelta = (tool: PendingTool, text: string) =>
  LLMEvent.toolInputDelta({
    id: tool.id,
    name: tool.name,
+    namespace: tool.namespace,
    text,
    input: Option.getOrElse(parsePartialInput(tool.input), () => ({})),
  })
@@ -85,6 +87,7 @@ const toolCall = (route: string, tool: PendingTool, inputOverride?: string) => {
        LLMEvent.toolCall({
          id: tool.id,
          name: tool.name,
+          namespace: tool.namespace,
          input,
          providerExecuted: tool.providerExecuted ? true : undefined,
          providerMetadata: tool.providerMetadata,
@@ -94,7 +97,12 @@ const toolCall = (route: string, tool: PendingTool, inputOverride?: string) => {
 }

 const finishEvents = (tool: PendingTool, event: ToolCall): ReadonlyArray<LLMEvent> => [
-  LLMEvent.toolInputEnd({ id: tool.id, name: tool.name, providerMetadata: tool.providerMetadata }),
+  LLMEvent.toolInputEnd({
+    id: tool.id,
+    name: tool.name,
+    namespace: tool.namespace,
+    providerMetadata: tool.providerMetadata,
+  }),
  event,
 ]

@@ -150,6 +158,7 @@ export const appendOrStart = <K extends StreamKey>(
  const tool = {
    id,
    name,
+    namespace: current?.namespace,
    input: `${current?.input ?? ""}${delta.text}`,
    providerExecuted: current?.providerExecuted,
    providerMetadata: current?.providerMetadata,
@@ -487,10 +487,14 @@ export function make<Body, Prepared, Frame, Event, State>(
 }

 const prepareRequest = (request: LLMRequest) => {
-  const original = applyCachePolicy(resolveRequestOptions(request))
+  const original = resolveRequestOptions(request)
  const sanitized = LLMRequest.update(original, sanitizeSurrogates({ ...LLMRequest.input(original), model: undefined }))
-  const tools = [...new Map(sanitized.tools.map((tool) => [tool.name, tool])).values()]
-  const resolved = tools.length === sanitized.tools.length ? sanitized : LLMRequest.update(sanitized, { tools })
+  // Deduplicate per sibling level; a tool and a namespace may share a name.
+  const dedupe = (tools: LLMRequest["tools"]): LLMRequest["tools"] =>
+    [...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 headers = resolved.model.route.headers?.({ request: resolved })
  return headers === undefined
    ? resolved
@@ -155,6 +155,7 @@ export const ToolInputStart = Schema.Struct({
  type: Schema.tag("tool-input-start"),
  id: ToolCallID,
  name: Schema.String,
+  namespace: Schema.optional(Schema.String),
  providerExecuted: Schema.optional(Schema.Boolean),
  providerMetadata: Schema.optional(ProviderMetadata),
 }).annotate({ identifier: "LLM.Event.ToolInputStart" })
@@ -164,6 +165,7 @@ export const ToolInputDelta = Schema.Struct({
  type: Schema.tag("tool-input-delta"),
  id: ToolCallID,
  name: Schema.String,
+  namespace: Schema.optional(Schema.String),
  text: Schema.String,
  /** Best-effort parse of all input fragments received through this delta. */
  input: Schema.optional(Schema.Unknown),
@@ -174,6 +176,7 @@ export const ToolInputEnd = Schema.Struct({
  type: Schema.tag("tool-input-end"),
  id: ToolCallID,
  name: Schema.String,
+  namespace: Schema.optional(Schema.String),
  providerMetadata: Schema.optional(ProviderMetadata),
 }).annotate({ identifier: "LLM.Event.ToolInputEnd" })
 export type ToolInputEnd = Schema.Schema.Type<typeof ToolInputEnd>
@@ -183,6 +186,7 @@ export const ToolInputError = Schema.Struct({
  type: Schema.tag("tool-input-error"),
  id: ToolCallID,
  name: Schema.String,
+  namespace: Schema.optional(Schema.String),
  raw: Schema.String,
 }).annotate({ identifier: "LLM.Event.ToolInputError" })
 export type ToolInputError = Schema.Schema.Type<typeof ToolInputError>
@@ -191,6 +195,7 @@ export const ToolCall = Schema.Struct({
  type: Schema.tag("tool-call"),
  id: ToolCallID,
  name: Schema.String,
+  namespace: Schema.optional(Schema.String),
  input: Schema.Unknown,
  providerExecuted: Schema.optional(Schema.Boolean),
  providerMetadata: Schema.optional(ProviderMetadata),
@@ -201,6 +206,7 @@ export const ToolResult = Schema.Struct({
  type: Schema.tag("tool-result"),
  id: ToolCallID,
  name: Schema.String,
+  namespace: Schema.optional(Schema.String),
  result: ToolResultValue,
  output: Schema.optional(ToolOutput),
  providerExecuted: Schema.optional(Schema.Boolean),
@@ -212,6 +218,7 @@ export const ToolError = Schema.Struct({
  type: Schema.tag("tool-error"),
  id: ToolCallID,
  name: Schema.String,
+  namespace: Schema.optional(Schema.String),
  message: Schema.String,
  error: Schema.optional(Schema.Defect()),
  providerMetadata: Schema.optional(ProviderMetadata),
@@ -385,6 +392,7 @@ interface ContentAssembly {

 interface ToolInputAssembly {
  readonly name: string
+  readonly namespace?: string
  readonly text: string
  readonly providerMetadata?: ProviderMetadata
 }
@@ -522,12 +530,17 @@ const reduceToolInputStart = (state: ResponseState, event: ToolInputStart): Resp
  ...state,
  toolInputs: {
    ...state.toolInputs,
-    [event.id]: { name: event.name, text: "", providerMetadata: event.providerMetadata },
+    [event.id]: {
+      name: event.name,
+      namespace: event.namespace,
+      text: "",
+      providerMetadata: event.providerMetadata,
+    },
  },
 })

 const reduceToolInputDelta = (state: ResponseState, event: ToolInputDelta): ResponseState => {
-  const current = state.toolInputs[event.id] ?? { name: event.name, text: "" }
+  const current = state.toolInputs[event.id] ?? { name: event.name, namespace: event.namespace, text: "" }
  return {
    ...state,
    toolInputs: { ...state.toolInputs, [event.id]: { ...current, text: current.text + event.text } },
@@ -535,7 +548,7 @@ const reduceToolInputDelta = (state: ResponseState, event: ToolInputDelta): Resp
 }

 const reduceToolInputEnd = (state: ResponseState, event: ToolInputEnd): ResponseState => {
-  const current = state.toolInputs[event.id] ?? { name: event.name, text: "" }
+  const current = state.toolInputs[event.id] ?? { name: event.name, namespace: event.namespace, text: "" }
  return {
    ...state,
    toolInputs: {
@@ -543,6 +556,7 @@ const reduceToolInputEnd = (state: ResponseState, event: ToolInputEnd): Response
      [event.id]: {
        ...current,
        name: event.name,
+        namespace: event.namespace,
        providerMetadata: event.providerMetadata ?? current.providerMetadata,
      },
    },
@@ -553,6 +567,7 @@ const toolCallContent = (event: ToolCall): ContentPart =>
  ToolCallPart.make({
    id: event.id,
    name: event.name,
+    namespace: event.namespace,
    input: event.input,
    ...(event.providerExecuted === undefined ? {} : { providerExecuted: event.providerExecuted }),
    ...(event.providerMetadata === undefined ? {} : { providerMetadata: event.providerMetadata }),
@@ -562,6 +577,7 @@ const toolResultContent = (event: ToolResult): ContentPart =>
  ToolResultPart.make({
    id: event.id,
    name: event.name,
+    namespace: event.namespace,
    result: event.result,
    ...(event.providerExecuted === undefined ? {} : { providerExecuted: event.providerExecuted }),
    ...(event.providerMetadata === undefined ? {} : { providerMetadata: event.providerMetadata }),
@@ -135,6 +135,7 @@ export const ToolCallPart = Object.assign(
    type: Schema.Literal("tool-call"),
    id: Schema.String,
    name: Schema.String,
+    namespace: Schema.optional(Schema.String),
    input: Schema.Unknown,
    providerExecuted: Schema.optional(Schema.Boolean),
    cache: Schema.optional(CacheHint),
@@ -152,6 +153,7 @@ export const ToolResultPart = Object.assign(
    type: Schema.Literal("tool-result"),
    id: Schema.String,
    name: Schema.String,
+    namespace: Schema.optional(Schema.String),
    result: ToolResultValue,
    providerExecuted: Schema.optional(Schema.Boolean),
    cache: Schema.optional(CacheHint),
@@ -168,6 +170,7 @@ export const ToolResultPart = Object.assign(
      type: "tool-result",
      id: input.id,
      name: input.name,
+      namespace: input.namespace,
      result: ToolResultValue.make(input.result, input.resultType),
      providerExecuted: input.providerExecuted,
      cache: input.cache,
@@ -266,7 +269,7 @@ export namespace Message {
    make({ role: "tool", content: ["type" in result ? result : ToolResultPart.make(result)] })
 }

-export class ToolDefinition extends Schema.Class<ToolDefinition>("LLM.ToolDefinition")({
+const toolDefinitionFields = {
  name: Schema.String,
  description: Schema.String,
  inputSchema: JsonSchema,
@@ -274,15 +277,71 @@ export class ToolDefinition extends Schema.Class<ToolDefinition>("LLM.ToolDefini
  cache: Schema.optional(CacheHint),
  metadata: Schema.optional(Schema.Record(Schema.String, Schema.Unknown)),
  native: Schema.optional(Schema.Record(Schema.String, Schema.Unknown)),
-}) {}
+}
+
+export type ToolDefinitionInput = Schema.Struct.Type<typeof toolDefinitionFields>
+
+export class ToolDefinition extends Schema.Class<ToolDefinition>("LLM.ToolDefinition")({
+  type: Schema.Literal("tool"),
+  ...toolDefinitionFields,
+}) {
+  constructor(input: ToolDefinitionInput) {
+    super({ ...input, type: "tool" })
+  }
+}

 export namespace ToolDefinition {
-  export type Input = ToolDefinition | ConstructorParameters<typeof ToolDefinition>[0]
+  export type Input = ToolDefinition | ToolDefinitionInput

  /** Normalize tool definition input into the canonical `ToolDefinition` class. */
  export const make = (input: Input) => (input instanceof ToolDefinition ? input : new ToolDefinition(input))
 }

+export type ToolNamespace = {
+  readonly type: "namespace"
+  readonly name: string
+  readonly description?: string
+  readonly tools: ReadonlyArray<ToolEntry>
+}
+
+export type ToolNamespaceInput = Omit<ToolNamespace, "type" | "tools"> & {
+  readonly tools: ReadonlyArray<ToolEntryInput>
+}
+export type ToolNamespaceEntryInput = ToolNamespaceInput & { readonly type: "namespace" }
+
+export const ToolNamespace: Schema.Codec<ToolNamespace> & {
+  readonly make: (input: ToolNamespace | ToolNamespaceInput) => ToolNamespace
+} = Object.assign(
+  Schema.Struct({
+    type: Schema.Literal("namespace"),
+    name: Schema.String,
+    description: Schema.optional(Schema.UndefinedOr(Schema.String)),
+    tools: Schema.Array(Schema.suspend((): Schema.Codec<ToolEntry> => ToolEntry)),
+  }).annotate({ identifier: "LLM.ToolNamespace" }),
+  {
+    make: (input: ToolNamespace | ToolNamespaceInput): ToolNamespace => ({
+      ...input,
+      type: "namespace",
+      tools: input.tools.map(ToolEntry.make),
+    }),
+  },
+)
+
+export type ToolEntry = ToolDefinition | ToolNamespace
+export type ToolEntryInput = ToolDefinition.Input | ToolNamespaceEntryInput
+export const ToolEntry: Schema.Codec<ToolEntry> & {
+  readonly make: (input: ToolEntryInput) => ToolEntry
+} = Object.assign(
+  Schema.Union([ToolDefinition, ToolNamespace]).pipe(
+    Schema.toTaggedUnion("type"),
+    Schema.annotate({ identifier: "LLM.ToolEntry" }),
+  ),
+  {
+    make: (input: ToolEntryInput): ToolEntry =>
+      "type" in input && input.type === "namespace" ? ToolNamespace.make(input) : ToolDefinition.make(input),
+  },
+)
+
 export class ToolChoice extends Schema.Class<ToolChoice>("LLM.ToolChoice")({
  type: Schema.Literals(["auto", "none", "required", "tool"]),
  name: Schema.optional(Schema.String),
@@ -312,7 +371,7 @@ const requestSchema = Schema.Struct({
  model: LanguageModelSchema,
  system: Schema.Array(SystemPart),
  messages: Schema.Array(Message),
-  tools: Schema.Array(ToolDefinition),
+  tools: Schema.Array(ToolEntry),
  toolChoice: Schema.optional(ToolChoice),
  generation: Schema.optional(GenerationOptions),
  providerOptions: Schema.optional(ProviderOptions),
@@ -37,7 +37,13 @@ function missingToolResults(calls: Iterable<ToolCallPart>) {
  return new Message({
    role: "tool",
    content: [...calls].map((call) =>
-      ToolResultPart.make({ id: call.id, name: call.name, result: MISSING_TOOL_RESULT, resultType: "error" }),
+      ToolResultPart.make({
+        id: call.id,
+        name: call.name,
+        namespace: call.namespace,
+        result: MISSING_TOOL_RESULT,
+        resultType: "error",
+      }),
    ),
  })
 }
@@ -47,7 +53,7 @@ function normalizeToolMessage(message: Message, pending: Map<string, ToolCallPar
    if (part.type !== "tool-result" || part.providerExecuted === true) return part
    const call = pending.get(part.id)
    if (call) pending.delete(part.id)
-    return normalizeToolResult(part, call?.name ?? part.name)
+    return normalizeToolResult(part, call)
  })
  if (content.length === 0) return undefined
  if (content.every((part, index) => part === message.content[index])) return message
@@ -61,8 +67,11 @@ function normalizeToolMessage(message: Message, pending: Map<string, ToolCallPar
  })
 }

-function normalizeToolResult(part: ToolResultPart, name: string): ToolResultPart {
-  const named = part.name === name ? part : { ...part, name }
+function normalizeToolResult(part: ToolResultPart, call: ToolCallPart | undefined): ToolResultPart {
+  const named =
+    call === undefined || (part.name === call.name && part.namespace === call.namespace)
+      ? part
+      : { ...part, name: call.name, namespace: call.namespace }
  if (named.result.type === "text" && named.result.value === "")
    return { ...named, result: { type: "text", value: EMPTY_TOOL_OUTPUT } }
  if (named.result.type === "error" && named.result.value === "")
@@ -21,10 +21,11 @@ export interface DispatchResult extends ToolSettlement {

 /** Execute one canonical tool call without owning provider IO or continuation. */
 export const dispatch = (tools: Tools, call: ToolCallPart): Effect.Effect<DispatchResult> => {
-  const tool = tools[call.name]
-  if (!tool) return Effect.succeed(result(call, { type: "error", value: `Unknown tool: ${call.name}` }))
+  const name = call.namespace === undefined ? call.name : `${call.namespace}.${call.name}`
+  const tool = tools[name]
+  if (!tool) return Effect.succeed(result(call, { type: "error", value: `Unknown tool: ${name}` }))
  if (!tool.execute)
-    return Effect.succeed(result(call, { type: "error", value: `Tool has no execute handler: ${call.name}` }))
+    return Effect.succeed(result(call, { type: "error", value: `Tool has no execute handler: ${name}` }))

  return decodeAndExecute(tool, call).pipe(
    Effect.map((value) => result(call, value)),
@@ -38,7 +39,11 @@ const decodeAndExecute = (tool: AnyTool, call: ToolCallPart): Effect.Effect<Tool
  tool._decode(call.input).pipe(
    Effect.mapError((error) => new ToolFailure({ message: `Invalid tool input: ${error.message}` })),
    Effect.flatMap((decoded) =>
-      tool.execute!(decoded, { id: call.id, name: call.name }).pipe(
+      tool.execute!(decoded, {
+        id: call.id,
+        name: call.name,
+        namespace: call.namespace,
+      }).pipe(
        Effect.flatMap((value) =>
          tool._encode(value).pipe(
            Effect.mapError(
@@ -71,6 +76,7 @@ const result = (call: ToolCallPart, value: ToolResultValueType | ToolSettlement,
            LLMEvent.toolError({
              id: call.id,
              name: call.name,
+              namespace: call.namespace,
              message: String(settlement.result.value),
              error,
              providerMetadata: call.providerMetadata,
@@ -78,6 +84,7 @@ const result = (call: ToolCallPart, value: ToolResultValueType | ToolSettlement,
            LLMEvent.toolResult({
              id: call.id,
              name: call.name,
+              namespace: call.namespace,
              result: settlement.result,
              providerMetadata: call.providerMetadata,
            }),
@@ -86,6 +93,7 @@ const result = (call: ToolCallPart, value: ToolResultValueType | ToolSettlement,
            LLMEvent.toolResult({
              id: call.id,
              name: call.name,
+              namespace: call.namespace,
              result: settlement.result,
              output: settlement.output,
              providerMetadata: call.providerMetadata,
@@ -16,6 +16,7 @@ export type ToolSchema<T> = Schema.Codec<T, any, never, never>
 export interface ToolExecuteContext {
  readonly id: ToolCallPart["id"]
  readonly name: ToolCallPart["name"]
+  readonly namespace?: ToolCallPart["namespace"]
 }

 export type ToolExecute<Parameters extends ToolSchema<any>, Success extends ToolSchema<any>> = (
@@ -215,6 +215,35 @@ describe("applyCachePolicy", () => {
    }),
  )

+  it.effect("deduplicates tools before counting cache hints", () =>
+    Effect.gen(function* () {
+      const manual = new CacheHint({ type: "ephemeral" })
+      const duplicate = (description: string) => ({
+        name: "lookup",
+        description,
+        inputSchema: { type: "object" },
+        cache: manual,
+      })
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model: anthropicModel,
+          tools: [
+            duplicate("first"),
+            duplicate("second"),
+            duplicate("third"),
+            duplicate("fourth"),
+            { name: "lookup", description: "final", inputSchema: { type: "object" } },
+          ],
+          cache: { tools: true },
+        }),
+      )
+
+      expect(prepared.body.tools).toEqual([
+        expect.objectContaining({ name: "lookup", description: "final", cache_control: { type: "ephemeral" } }),
+      ])
+    }),
+  )
+
  it.effect("auto policy preserves manual CacheHints on other parts", () =>
    Effect.gen(function* () {
      const prepared = yield* compileRequest(
@@ -281,6 +310,30 @@ describe("applyCachePolicy", () => {
    }),
  )

+  test("marks the final leaf inside a tool namespace", () => {
+    const request = LLM.request({
+      model: anthropicModel,
+      tools: [
+        {
+          type: "namespace",
+          name: "crm",
+          tools: [
+            { name: "lookup", description: "lookup", inputSchema: {} },
+            { name: "orders", description: "orders", inputSchema: {} },
+          ],
+        },
+      ],
+      cache: { tools: true },
+    })
+    const applied = applyCachePolicy(request)
+    const namespace = applied.tools[0]
+
+    expect(namespace?.type).toBe("namespace")
+    if (namespace?.type !== "namespace") throw new Error("Expected namespace")
+    expect(namespace.tools[0]).not.toHaveProperty("cache")
+    expect(namespace.tools[1]).toHaveProperty("cache", { type: "ephemeral" })
+  })
+
  it.effect("ttlSeconds in the policy flows through to wire markers", () =>
    Effect.gen(function* () {
      const prepared = yield* compileRequest(
@@ -1,8 +1,16 @@
 import { describe, expect, test } from "bun:test"
 import { Effect, Ref, Schema } from "effect"
 import { HttpClientRequest, HttpClientResponse } from "effect/unstable/http"
-import { LLM, LLMRequest, Message, ToolCallPart, ToolDefinition, mergeProviderOptions } from "../src/index.js"
-import { AnthropicMessages, OpenAIChat } from "../src/protocols.js"
+import {
+  LLM,
+  LLMRequest,
+  Message,
+  ToolCallPart,
+  ToolDefinition,
+  ToolNamespace,
+  mergeProviderOptions,
+} from "../src/index.js"
+import { AnthropicMessages, OpenAIChat, OpenAIResponses } from "../src/protocols.js"
 import { Auth, LLMClient } from "../src/route.js"
 import { compileRequest } from "../src/route/client.js"
 import { it } from "./lib/effect.js"
@@ -106,6 +114,58 @@ describe("request option precedence", () => {
    }),
  )

+  it.effect("deduplicates tools within each namespace", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model: OpenAIResponses.route.model({ id: "gpt-5.4" }),
+          tools: [
+            ToolDefinition.make({ name: "crm", description: "Top-level CRM tool", inputSchema: {} }),
+            ToolNamespace.make({
+              name: "crm",
+              description: "CRM tools",
+              tools: [
+                ToolDefinition.make({ name: "lookup", description: "old", inputSchema: {} }),
+                ToolDefinition.make({ name: "search", description: "search", inputSchema: {} }),
+                ToolDefinition.make({ name: "lookup", description: "new", inputSchema: {} }),
+              ],
+            }),
+            ToolNamespace.make({
+              name: "support",
+              description: "Support tools",
+              tools: [ToolDefinition.make({ name: "lookup", description: "support", inputSchema: {} })],
+            }),
+          ],
+        }),
+      )
+
+      expect(prepared.body.tools).toEqual([
+        {
+          type: "function",
+          name: "crm",
+          description: "Top-level CRM tool",
+          parameters: {},
+          strict: false,
+        },
+        {
+          type: "namespace",
+          name: "crm",
+          description: "CRM tools",
+          tools: [
+            { type: "function", name: "lookup", description: "new", parameters: {}, strict: false },
+            { type: "function", name: "search", description: "search", parameters: {}, strict: false },
+          ],
+        },
+        {
+          type: "namespace",
+          name: "support",
+          description: "Support tools",
+          tools: [{ type: "function", name: "lookup", description: "support", parameters: {}, strict: false }],
+        },
+      ])
+    }),
+  )
+
  it.effect("normalizes tool history before protocol lowering", () =>
    Effect.gen(function* () {
      const prepared = yield* compileRequest(
@@ -1,5 +1,6 @@
 import { describe, expect, test } from "bun:test"
-import { CacheHint, LLM, LLMResponse } from "../src/index.js"
+import { Schema } from "effect"
+import { CacheHint, LLM, LLMResponse, ToolEntry, ToolNamespace } from "../src/index.js"
 import * as OpenAIChat from "../src/protocols/openai-chat.js"
 import * as OpenAIResponses from "../src/protocols/openai-responses.js"
 import {
@@ -17,6 +18,52 @@ const chatRoute = OpenAIChat.route
 const responsesRoute = OpenAIResponses.route

 describe("llm constructors", () => {
+  test("normalizes recursive tool namespaces", () => {
+    const request = LLM.request({
+      model: LanguageModel.make({ id: "fake-model", provider: "fake", route: responsesRoute }),
+      tools: [
+        {
+          type: "namespace",
+          name: "crm",
+          description: "Customer management",
+          tools: [
+            { name: "lookup", description: "Look up a customer", inputSchema: { type: "object" } },
+            {
+              type: "namespace",
+              name: "orders",
+              tools: [{ name: "list", description: "List orders", inputSchema: { type: "object" } }],
+            },
+          ],
+        },
+      ],
+    })
+
+    expect(request.tools[0]).toEqual({
+      type: "namespace",
+      name: "crm",
+      description: "Customer management",
+      tools: [
+        expect.objectContaining({ type: "tool", name: "lookup" }),
+        {
+          type: "namespace",
+          name: "orders",
+          description: undefined,
+          tools: [expect.objectContaining({ type: "tool", name: "list" })],
+        },
+      ],
+    })
+    expect(request.tools[0]).toEqual(
+      ToolNamespace.make({
+        name: "crm",
+        description: "Customer management",
+        tools: request.tools[0]!.type === "namespace" ? request.tools[0].tools : [],
+      }),
+    )
+    expect(Schema.decodeUnknownSync(ToolEntry)(Schema.encodeUnknownSync(ToolEntry)(request.tools[0]))).toEqual(
+      request.tools[0],
+    )
+  })
+
  test("builds canonical schema classes from ergonomic input", () => {
    const request = LLM.request({
      id: "req_1",
@@ -1,6 +1,6 @@
 import { expect } from "bun:test"
 import { Effect, Schema } from "effect"
-import { LLM, LLMRequest, Message } from "../../src/index.js"
+import { LLM, LLMRequest, Message, ToolDefinition } from "../../src/index.js"
 import { LLMClient, Route } from "../../src/route/client.js"
 import { Auth } from "../../src/route/auth.js"
 import { Endpoint } from "../../src/route/endpoint.js"
@@ -134,7 +134,12 @@ for (const model of [
        [
          LLMRequest.update(request, {
            tools: [
-              { name: "unsupported", description: "Generation only", inputSchema: {}, native: { unsupported: {} } },
+              ToolDefinition.make({
+                name: "unsupported",
+                description: "Generation only",
+                inputSchema: {},
+                native: { unsupported: {} },
+              }),
            ],
          }),
          "InvalidRequest",
@@ -326,7 +326,6 @@ describe("Open Responses basic-item lifecycles", () => {
      ])
    }),
  )
-
  it.effect("mints an id for a done-only tool that never had one", () =>
    Effect.gen(function* () {
      const events = yield* collect(
@@ -357,9 +356,16 @@ describe("Open Responses basic-item lifecycles", () => {
      const events = yield* collect({ type: "response.output_item.done", item }, completed)
      const providerMetadata = { "openai-compatible": { itemId: "fc_1" } }
      expect(events.filter((event) => event.type.startsWith("tool-"))).toEqual([
-        { type: "tool-input-start", id: "call_1", name: "lookup", providerMetadata },
-        { type: "tool-input-end", id: "call_1", name: "lookup", providerMetadata },
-        { type: "tool-call", id: "call_1", name: "lookup", input: { query: "weather" }, providerMetadata },
+        { type: "tool-input-start", id: "call_1", name: "lookup", namespace: undefined, providerMetadata },
+        { type: "tool-input-end", id: "call_1", name: "lookup", namespace: undefined, providerMetadata },
+        {
+          type: "tool-call",
+          id: "call_1",
+          name: "lookup",
+          namespace: undefined,
+          input: { query: "weather" },
+          providerMetadata,
+        },
      ])
      expect(events.filter(LLMEvent.is.finish)).toEqual([
        {
@@ -171,6 +171,66 @@ describe("Open Responses-compatible route", () => {
    }),
  )

+  it.effect("flattens tool namespaces", () =>
+    Effect.gen(function* () {
+      const model = configure({ apiKey: "test-key", baseURL: "https://responses.example.test/v1" }).model(
+        "example-model",
+      )
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model,
+          tools: [
+            {
+              type: "namespace",
+              name: "acme",
+              tools: [
+                {
+                  type: "namespace",
+                  name: "billing",
+                  tools: [ToolDefinition.make({ name: "lookup", description: "Lookup billing", inputSchema: {} })],
+                },
+                ToolDefinition.make({ name: "users", description: "Lookup users", inputSchema: {} }),
+              ],
+            },
+          ],
+        }),
+      )
+
+      expect(prepared.body.tools).toEqual([
+        {
+          type: "function",
+          name: "acme_billing_lookup",
+          description: "Lookup billing",
+          parameters: {},
+          strict: false,
+        },
+        { type: "function", name: "acme_users", description: "Lookup users", parameters: {}, strict: false },
+      ])
+    }),
+  )
+
+  it.effect("flattens tool namespaces in history", () =>
+    Effect.gen(function* () {
+      const model = configure({ apiKey: "test-key", baseURL: "https://responses.example.test/v1" }).model(
+        "example-model",
+      )
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model,
+          messages: [
+            Message.assistant({ type: "tool-call", id: "call_1", name: "lookup", namespace: "crm", input: {} }),
+            Message.tool({ id: "call_1", name: "lookup", namespace: "crm", result: "done", resultType: "text" }),
+          ],
+        }),
+      )
+
+      expect(prepared.body.input).toEqual([
+        { type: "function_call", call_id: "call_1", name: "crm_lookup", namespace: undefined, arguments: "{}" },
+        { type: "function_call_output", call_id: "call_1", output: "done" },
+      ])
+    }),
+  )
+
  it.effect("lowers canonical parallel tool control", () =>
    Effect.gen(function* () {
      const model = configure({
@@ -12,6 +12,7 @@ import {
  LanguageModel,
  ToolCallPart,
  ToolDefinition,
+  ToolNamespace,
  ToolResultPart,
  TransportError,
  Usage,
@@ -143,6 +144,94 @@ describe("OpenAI Responses route", () => {
    }),
  )

+  it.effect("lowers tool namespaces without flattening leaf names", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model,
+          prompt: "Find a customer and their orders.",
+          tools: [
+            ToolNamespace.make({
+              name: "crm",
+              description: "Customer management",
+              tools: [
+                ToolDefinition.make({ name: "lookup", description: "Look up a customer", inputSchema: {} }),
+                ToolDefinition.make({ name: "orders", description: "List customer orders", inputSchema: {} }),
+              ],
+            }),
+          ],
+        }),
+      )
+
+      expect(prepared.body.tools).toEqual([
+        {
+          type: "namespace",
+          name: "crm",
+          description: "Customer management",
+          tools: [
+            { type: "function", name: "lookup", description: "Look up a customer", parameters: {}, strict: false },
+            { type: "function", name: "orders", description: "List customer orders", parameters: {}, strict: false },
+          ],
+        },
+      ])
+    }),
+  )
+
+  it.effect("flattens nested levels within a native tool namespace", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model,
+          tools: [
+            {
+              type: "namespace",
+              name: "crm",
+              description: "Customer management",
+              tools: [
+                {
+                  type: "namespace",
+                  name: "orders",
+                  description: "Order management",
+                  tools: [ToolDefinition.make({ name: "list", description: "List orders", inputSchema: {} })],
+                },
+              ],
+            },
+          ],
+        }),
+      )
+
+      expect(prepared.body.tools).toEqual([
+        {
+          type: "namespace",
+          name: "crm",
+          description: "Customer management",
+          tools: [{ type: "function", name: "orders_list", description: "List orders", parameters: {}, strict: false }],
+        },
+      ])
+    }),
+  )
+
+  it.effect("defaults tool namespace descriptions", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model,
+          tools: [
+            {
+              type: "namespace",
+              name: "crm",
+              tools: [ToolDefinition.make({ name: "lookup", description: "Look up a customer", inputSchema: {} })],
+            },
+          ],
+        }),
+      )
+
+      expect(prepared.body.tools).toEqual([
+        expect.objectContaining({ type: "namespace", name: "crm", description: "Tools in the crm namespace." }),
+      ])
+    }),
+  )
+
  it.effect("rejects invalid hosted image generation options locally", () =>
    Effect.gen(function* () {
      const error = yield* compileRequest(
@@ -2130,6 +2219,71 @@ describe("OpenAI Responses route", () => {
    }),
  )

+  it.effect("preserves tool namespaces through streaming and history replay", () =>
+    Effect.gen(function* () {
+      const item = {
+        type: "function_call",
+        id: "fc_1",
+        call_id: "call_1",
+        namespace: "crm",
+        name: "lookup",
+        arguments: "",
+      }
+      const response = yield* LLMClient.generate(request).pipe(
+        Effect.provide(
+          fixedResponse(
+            sseEvents(
+              { type: "response.output_item.added", output_index: 0, item },
+              {
+                type: "response.function_call_arguments.delta",
+                output_index: 0,
+                item_id: "fc_1",
+                delta: '{"id":"123"}',
+              },
+              {
+                type: "response.output_item.done",
+                output_index: 0,
+                item: { ...item, arguments: '{"id":"123"}' },
+              },
+              { type: "response.completed", response: { id: "resp_1" } },
+            ),
+          ),
+        ),
+      )
+
+      const toolEvents = response.events.filter((event) => event.type.startsWith("tool-"))
+      expect(toolEvents).toEqual([
+        expect.objectContaining({ type: "tool-input-start", name: "lookup", namespace: "crm" }),
+        expect.objectContaining({ type: "tool-input-delta", name: "lookup", namespace: "crm" }),
+        expect.objectContaining({ type: "tool-input-end", name: "lookup", namespace: "crm" }),
+        expect.objectContaining({ type: "tool-call", name: "lookup", namespace: "crm", input: { id: "123" } }),
+      ])
+      expect(response.message.content).toEqual([
+        expect.objectContaining({ type: "tool-call", name: "lookup", namespace: "crm", input: { id: "123" } }),
+      ])
+
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model,
+          messages: [
+            response.message,
+            Message.tool({ id: "call_1", name: "lookup", namespace: "crm", result: { customer: "Ada" } }),
+          ],
+        }),
+      )
+      expect(prepared.body.input).toEqual([
+        {
+          type: "function_call",
+          id: "fc_1",
+          call_id: "call_1",
+          namespace: "crm",
+          name: "lookup",
+          arguments: '{"id":"123"}',
+        },
+        { type: "function_call_output", call_id: "call_1", output: '{"customer":"Ada"}' },
+      ])
+    }),
+  )
  it.effect("routes reasoning summary events by output index", () =>
    Effect.gen(function* () {
      const response = yield* LLMClient.generate(request).pipe(
@@ -15,13 +15,7 @@ describe("tool history normalization", () => {
      Message.assistant(toolCall("trailing")),
    ])

-    expect(normalized.map((message) => message.role)).toEqual([
-      "assistant",
-      "tool",
-      "tool",
-      "user",
-      "assistant",
-    ])
+    expect(normalized.map((message) => message.role)).toEqual(["assistant", "tool", "tool", "user", "assistant"])
    expect(normalized[1]?.content[0]).toMatchObject({ type: "tool-result", id: "first", name: "first" })
    expect(normalized[2]?.content).toEqual([
      { type: "tool-result", id: "second", name: "second", result: { type: "error", value: "Tool result missing" } },
@@ -74,4 +68,13 @@ describe("tool history normalization", () => {

    expect(normalizeToolHistory([orphan, hosted])).toEqual([orphan, hosted])
  })
+
+  test("uses a matching call as the complete tool identity", () => {
+    const normalized = normalizeToolHistory([
+      Message.assistant(ToolCallPart.make({ id: "call_1", name: "lookup", input: {} })),
+      Message.tool(ToolResultPart.make({ id: "call_1", name: "wrong", namespace: "stale", result: "done" })),
+    ])
+
+    expect(normalized[1]?.content[0]).toMatchObject({ name: "lookup", namespace: undefined })
+  })
 })
@@ -7,6 +7,7 @@ import {
  LLMEvent,
  LLMRequest,
  LLMResponse,
+  ToolCallPart,
  ToolChoice,
  ToolOutput,
  toDefinitions,
@@ -36,6 +37,27 @@ const baseRequest = LLM.request({
 })
 const weatherFailureCause = new Error("weather lookup denied")

+test("dispatches namespaced calls by qualified identity", async () => {
+  let context: ToolExecuteContext | undefined
+  const lookup = Tool.make({
+    description: "Look up a customer.",
+    parameters: Schema.Struct({}),
+    success: Schema.String,
+    execute: (_, value) => {
+      context = value
+      return Effect.succeed("customer")
+    },
+  })
+  const call = ToolCallPart.make({ id: "call_1", namespace: "crm", name: "lookup", input: {} })
+  const result = await Effect.runPromise(
+    ToolRuntime.dispatch({ "crm.lookup": lookup, lookup: schema_only_weather }, call),
+  )
+
+  expect(result.result).toEqual({ type: "text", value: "customer" })
+  expect(context).toEqual({ id: "call_1", namespace: "crm", name: "lookup" })
+  expect(result.events).toEqual([expect.objectContaining({ type: "tool-result", namespace: "crm", name: "lookup" })])
+})
+
 const get_weather = Tool.make({
  description: "Get current weather for a city.",
  parameters: Schema.Struct({ city: Schema.String }),
@@ -134,7 +134,7 @@ for (const viewport of [
      await expect(page).toHaveURL(pending.url)
      await expect(pending.message).toHaveAttribute("data-timeline-part-id", `${pending.messageID}:text:0`)
      await expect(pending.shimmer).toHaveAttribute("data-active", "true")
-      await expect(pending.title).toHaveText("New session")
+      await expect(pending.title).toHaveText("Session")
      await expect(editor).toHaveText(followUp)
      expect(mock.calls).toEqual(["worktree"])

@@ -238,7 +238,7 @@ for (const direction of ["ltr", "rtl"]) {
          !frame.message ||
          !frame.spinner ||
          frame.draft !== followUp ||
-          !["New session", "Created workspace session"].includes(frame.title ?? ""),
+          !["Session", "Created workspace session"].includes(frame.title ?? ""),
      ),
    ).toEqual([])
    const after = await title.boundingBox()
@@ -598,7 +598,7 @@ async function submitPending(page: Page, mock: Awaited<ReturnType<typeof openDra
  const shimmer = preparing.getByRole("status").locator('[data-component="text-shimmer"]')
  const title = preparing.getByRole("heading", { level: 1 })
  await expect(preparing).toBeVisible()
-  await expect(title).toHaveText("New session")
+  await expect(title).toHaveText("Session")
  await expect(page.locator('[data-component="composer-editor"]')).toBeEditable()
  await expect(page.locator('[data-action="composer-submit"]')).toBeDisabled()
  await expect(preparing.locator('[data-component="user-message"]')).toHaveCount(1)
@@ -1,4 +1,4 @@
-import { onMount } from "solid-js"
+import { onCleanup, onMount } from "solid-js"
 import { makeEventListener } from "@solid-primitives/event-listener"
 import type { ComposerAttachment, ComposerPrompt } from "../types"

@@ -78,6 +78,7 @@ export type ComposerAttachmentConfig = {
  onError: (error: unknown) => void
  readClipboardImage?: () => Promise<File | null>
  getPathForFile?: (file: File) => string
+  onDragCancel?: (callback: () => void) => () => void
  store?: (file: File) => Promise<{ id: string; url: string }>
 }

@@ -90,6 +91,9 @@ export function createComposerAttachments(
    setDraggingType: (type: "image" | "@mention" | null) => void
  },
 ) {
+  const clearDrag = () => {
+    input.setDraggingType(null)
+  }
  const capture = () => {
    const prompt = input.capture()
    const editor = input.editor()
@@ -178,7 +182,7 @@ export function createComposerAttachments(
  const handleDrop = async (event: DragEvent) => {
    if (input.isDialogActive()) return
    event.preventDefault()
-    input.setDraggingType(null)
+    clearDrag()
    const plainText = event.dataTransfer?.getData("text/plain")
    if (plainText?.startsWith("file:")) {
      const path = plainText.slice("file:".length)
@@ -191,6 +195,8 @@ export function createComposerAttachments(
  }

  onMount(() => {
+    const cancel = input.onDragCancel?.(clearDrag)
+    if (cancel) onCleanup(cancel)
    makeEventListener(document, "dragover", (event) => {
      if (input.isDialogActive()) return
      event.preventDefault()
@@ -198,7 +204,10 @@ export function createComposerAttachments(
      else if (event.dataTransfer?.types.includes("text/plain")) input.setDraggingType("@mention")
    })
    makeEventListener(document, "dragleave", (event) => {
-      if (!input.isDialogActive() && !event.relatedTarget) input.setDraggingType(null)
+      if (!input.isDialogActive() && !event.relatedTarget) clearDrag()
+    })
+    makeEventListener(document, "keydown", (event) => {
+      if (event.key === "Escape") clearDrag()
    })
    makeEventListener(document, "drop", handleDrop)
  })
@@ -118,7 +118,6 @@ export function ComposerEditor(props: ComposerEditorProps) {
        class="group/composer relative min-h-[96px] w-full overflow-clip rounded-xl bg-v2-background-bg-base"
        classList={{
          "shadow-[var(--v2-elevation-raised)]": !props.borderUnderlay,
-          "border border-v2-icon-icon-info border-dashed": state.drag === "active",
        }}
        onSubmit={(event) => {
          event.preventDefault()
@@ -129,12 +128,6 @@ export function ComposerEditor(props: ComposerEditorProps) {
        onDragLeave={props.controller.onDragLeave}
        onDrop={props.controller.onDrop}
      >
-        <Show when={state.drag === "active"}>
-          <div class="pointer-events-none absolute inset-0 z-20 grid place-items-center rounded-xl bg-v2-background-bg-base/90 text-v2-text-text-base">
-            {i18n.t("ui.promptInput.dropFiles")}
-          </div>
-        </Show>
-
        <Show when={state.mode === "normal"}>
          <ComposerAttachments
            attachments={props.controller.attachments()}
@@ -42,9 +42,14 @@ export function createComposerModel(adapter: ComposerAdapter, options?: { queue?

  const interaction = createComposerEditorState(prompt.mode.current())
  createEffect(
-    on(adapter.ready, (ready) => {
-      if (ready) interaction[1]("mode", prompt.mode.current())
-    }),
+    on(
+      () => (adapter.ready() ? prompt.mode.current() : undefined),
+      (mode) => {
+        if (!mode) return
+        // Project external draft changes without another mode write clearing restored retry metadata.
+        interaction[1](mode === "shell" ? { mode, popover: { type: "closed" } } : { mode })
+      },
+    ),
  )
  const mode = () => interaction[0].mode
  const history = createComposerHistory()
@@ -346,6 +351,7 @@ export function createComposerModel(adapter: ComposerAdapter, options?: { queue?
        }),
      readClipboardImage: platform.readClipboardImage,
      getPathForFile: platform.getPathForFile,
+      onDragCancel: platform.onDragCancel,
      store: platform.draftStore?.putBlob,
    },
    view: {
@@ -319,6 +319,69 @@
    }
  }

+  @keyframes session-dropzone-enter {
+    from {
+      opacity: 0;
+    }
+  }
+
+  @keyframes session-dropzone-content-enter {
+    from {
+      opacity: 0;
+      transform: translateY(4px) scale(0.96);
+    }
+  }
+
+  @keyframes session-dropzone-upload-enter {
+    from {
+      opacity: 0;
+      transform: translateY(4px) scale(0.92);
+    }
+  }
+
+  @keyframes session-dropzone-stripes-drift {
+    to {
+      background-position: 33.941px 0;
+    }
+  }
+
+  [data-component="session-dropzone"][data-visible="true"] {
+    animation: session-dropzone-enter 200ms cubic-bezier(0.215, 0.61, 0.355, 1);
+  }
+
+  [data-component="session-dropzone"][data-visible="true"] [data-slot="session-dropzone-content"] {
+    animation: session-dropzone-content-enter 200ms cubic-bezier(0.215, 0.61, 0.355, 1);
+  }
+
+  [data-component="session-dropzone"][data-visible="true"] [data-slot="session-dropzone-upload"] {
+    animation: session-dropzone-upload-enter 240ms cubic-bezier(0.215, 0.61, 0.355, 1);
+  }
+
+  [data-component="session-dropzone"][data-visible="true"] [data-slot="session-dropzone-stripes"] {
+    animation: session-dropzone-stripes-drift 3s linear infinite;
+  }
+
+  [data-component="session-dropzone"] {
+    --session-dropzone-wash: 4%;
+    --session-dropzone-stripe: 7%;
+    --session-dropzone-card: var(--v2-background-bg-base);
+  }
+
+  [data-color-scheme="dark"] [data-component="session-dropzone"] {
+    --session-dropzone-wash: 6%;
+    --session-dropzone-stripe: 14%;
+    --session-dropzone-card: var(--v2-background-bg-layer-01);
+  }
+
+  @media (prefers-reduced-motion: reduce) {
+    [data-component="session-dropzone"][data-visible="true"],
+    [data-component="session-dropzone"][data-visible="true"] [data-slot="session-dropzone-content"],
+    [data-component="session-dropzone"][data-visible="true"] [data-slot="session-dropzone-upload"],
+    [data-component="session-dropzone"][data-visible="true"] [data-slot="session-dropzone-stripes"] {
+      animation: none;
+    }
+  }
+
  [data-slot="home-projects-scroll"] {
    timeline-scope: --home-projects-scroll;
  }
@@ -59,6 +59,9 @@ type PlatformBase = {
  /** Resolve the native source path for a desktop File. */
  getPathForFile?(file: File): string

+  /** Observe native drag cancellation that does not reach the renderer event loop. */
+  onDragCancel?(callback: () => void): () => void
+
  /** Open a native save file dialog and write content to the selected path (desktop only) */
  saveFile?(opts: SaveFilePickerOptions, content: string): Promise<boolean>

@@ -4,16 +4,14 @@ import { useComposerState } from "@/composer/persistence"
 import { useData } from "@/runtime/server/current"
 import { useServerSDK } from "@/runtime/server/client"
 import { useWorkspaceLocation } from "@/workspaces/location"
-import type { SessionModel } from "../model"

 export function createActiveComposerAdapter(input: {
-  session: SessionModel
+  sessionID: string
  controls: Accessor<ComposerControls>
  submitted: () => void
  setEditor: (element: HTMLDivElement) => void
 }) {
-  const id = input.session.identity.params.id
-  if (!id) throw new Error("Active Composer requires a Session ID")
+  const id = input.sessionID

  const prompt = useComposerState()
  prompt.current()
@@ -0,0 +1,57 @@
+import { createEffect, createMemo, on, type Accessor } from "solid-js"
+import type { ComposerControls } from "@/composer/adapter"
+import { setCursorPosition } from "@/composer/editor/dom"
+import { createComposerModel } from "@/composer/model"
+import { useSettings } from "@/settings/model"
+import { createActiveComposerAdapter } from "./adapter"
+import { createSessionQueue } from "./queue"
+import { createSessionComposerRegionController } from "./session-composer-region-controller"
+
+export function createSessionComposerController(input: {
+  sessionID: string
+  controls: Accessor<ComposerControls>
+  dock: Parameters<typeof createSessionComposerRegionController>[0]
+}) {
+  const settings = useSettings()
+  const region = createSessionComposerRegionController(input.dock)
+  let editor: HTMLDivElement | undefined
+  const adapter = createActiveComposerAdapter({
+    sessionID: input.sessionID,
+    controls: input.controls,
+    submitted: region.onResponseSubmit,
+    setEditor: (element) => {
+      editor = element
+      region.setPromptRef(element)
+    },
+  })
+  const queue = createSessionQueue({
+    sessionID: input.sessionID,
+    draft: adapter.state,
+    working: adapter.working,
+    behavior: settings.general.followUpBehavior,
+    restoreFocus: (cursor) => {
+      const target = editor
+      if (!target) return
+      requestAnimationFrame(() => {
+        target.focus()
+        setCursorPosition(target, cursor)
+      })
+    },
+  })
+  const composer = createComposerModel(adapter, { queue })
+  const editable = createMemo(() => region.showComposer() && !region.child())
+  // Requests hide the view without disposing its draft or queue edit.
+  createEffect(on(editable, () => composer.onDragLeave()))
+
+  return {
+    region,
+    queue,
+    composer,
+    drop: {
+      active: () => editable() && composer.state.drag === "active",
+      input: () => composer.model.selection.current()?.capabilities.input,
+    },
+  }
+}
+
+export type SessionComposerController = ReturnType<typeof createSessionComposerController>
@@ -4,7 +4,6 @@ import { useMutation } from "@tanstack/solid-query"
 import type { SessionInboxInfo } from "@opencode-ai/client/promise"
 import { SessionMessage } from "@opencode-ai/schema/session-message"
 import type { ComposerDelivery } from "@/composer/adapter"
-import type { ComposerModel } from "@/composer/model"
 import type { ComposerStateTarget } from "@/composer/submission-state"
 import type { ImageAttachmentPart, Prompt } from "@/composer/state"
 import { clonePrompt, promptLength } from "@/composer/prompt-parts"
@@ -30,7 +29,7 @@ export function createSessionQueue(input: {
  draft: ComposerStateTarget
  working: Accessor<boolean>
  behavior: Accessor<ComposerDelivery>
-  composer: Accessor<ComposerModel | undefined>
+  restoreFocus: (cursor: number) => void
 }) {
  const data = useData()
  const server = useServerSDK()
@@ -159,9 +158,9 @@ export function createSessionQueue(input: {
      },
    })
    const text = queuedPromptText(item)
-    input.composer()?.dispatch({ type: "mode.normal" })
+    input.draft.mode.set("normal")
    input.draft.set([{ type: "text", content: text, start: 0, end: text.length }], text.length)
-    input.composer()?.restoreFocus(text.length)
+    input.restoreFocus(text.length)
    return true
  }
  const cancelEdit = () => {
@@ -170,10 +169,10 @@ export function createSessionQueue(input: {
    setState("editing", undefined)
    // Mode first, then prompt, then retry: mode and prompt writes both clear
    // the retry marker.
-    input.composer()?.dispatch({ type: editing.stash.mode === "shell" ? "mode.shell" : "mode.normal" })
+    input.draft.mode.set(editing.stash.mode)
    input.draft.set(editing.stash.prompt, editing.stash.cursor)
    if (editing.stash.retry) input.draft.retry.set(editing.stash.retry)
-    input.composer()?.restoreFocus(editing.stash.cursor)
+    input.restoreFocus(editing.stash.cursor)
  }
  const confirmEdit = (delivery: ComposerDelivery) => {
    const editing = state.editing
@@ -4,9 +4,8 @@ import { useDialog } from "@opencode-ai/ui/context/dialog"
 import { isScrollKeyTarget, scrollKey, scrollKeyOwner } from "@opencode-ai/ui/scroll-view"
 import { makeEventListener } from "@solid-primitives/event-listener"
 import { useNavigate } from "@solidjs/router"
-import { createEffect, on, onMount } from "solid-js"
+import { createEffect, createMemo, on, onMount, type Accessor } from "solid-js"
 import { Composer } from "@/composer/composer"
-import { createComposerModel, type ComposerModel } from "@/composer/model"
 import { useComposerState } from "@/composer/persistence"
 import { createComposerControls } from "@/composer/selection"
 import { setCursorPosition } from "@/composer/editor/dom"
@@ -25,18 +24,16 @@ import { restorePromptModel, syncPromptModel, syncSessionModel } from "../sessio
 import type { SessionTimelineInteraction } from "../timeline/interaction"
 import { createSessionRevert } from "../revert"
 import { SessionComposerRegion } from "./session-composer-region"
-import { createSessionComposerRegionController } from "./session-composer-region-controller"
-import { createActiveComposerAdapter } from "./adapter"
-import { createSessionQueue } from "./queue"
+import { createSessionComposerController, type SessionComposerController } from "./controller"
 import { SessionQueuePanel } from "./queue-panel"
 import { resolveSessionComposerSelection } from "./selection"
 import { createSessionRequestModel } from "../requests/model"
-import { useSettings } from "@/settings/model"

 export function createActiveSessionRegion(input: {
  session: SessionModel
  screen: SessionScreenLayout
  timeline: SessionTimelineInteraction
+  visible: Accessor<boolean>
 }) {
  const command = useCommand()
  const dialog = useDialog()
@@ -180,7 +177,30 @@ export function createActiveSessionRegion(input: {
    },
  ])

+  const dock = {
+    state,
+    parentID: input.session.data.parentID,
+    centered: input.screen.centered,
+    onResponseSubmit: input.timeline.actions.resume,
+    openParent,
+    setPromptRef: (element: HTMLDivElement) => {
+      promptRef = element
+    },
+    setDockRef: input.timeline.view.setDockRef,
+  }
+  const active = createMemo(
+    on(
+      () => (input.visible() ? input.session.identity.sessionID() : undefined),
+      (sessionID) => (sessionID ? createSessionComposerController({ sessionID, controls, dock }) : undefined),
+    ),
+  )
+
  return {
+    active,
+    drop: {
+      active: () => active()?.drop.active() ?? false,
+      input: () => active()?.drop.input(),
+    },
    actions: {
      timeline: {
        get revert() {
@@ -190,76 +210,25 @@ export function createActiveSessionRegion(input: {
        openAttachment,
      } satisfies SessionUserActions,
    },
-    region: {
-      centered: input.screen.centered,
-      openParent,
-      prompt,
-      setDockRef: input.timeline.view.setDockRef,
-      setPromptRef: (element: HTMLDivElement) => {
-        promptRef = element
-      },
-      state,
-    },
-    input: {
-      controls,
-      setPromptRef: (element: HTMLDivElement) => {
-        promptRef = element
-      },
-    },
-    submitted: () => input.timeline.actions.resume(),
+    requests: state,
    workspaceMoveEligible: () => true,
  }
 }

 export type ActiveSessionRegionModel = ReturnType<typeof createActiveSessionRegion>

-export function ActiveSessionComposerRegion(props: {
-  model: ActiveSessionRegionModel
-  session: SessionModel
-  onResponseSubmit: () => void
-}) {
-  const settings = useSettings()
-  const region = createSessionComposerRegionController({
-    state: props.model.region.state,
-    parentID: props.session.data.parentID,
-    centered: props.model.region.centered,
-    onResponseSubmit: props.onResponseSubmit,
-    openParent: props.model.region.openParent,
-    setPromptRef: props.model.region.setPromptRef,
-    setDockRef: props.model.region.setDockRef,
-  })
-  const adapter = createActiveComposerAdapter({
-    session: props.session,
-    controls: props.model.input.controls,
-    submitted: props.model.submitted,
-    setEditor: props.model.input.setPromptRef,
-  })
-  let composer: ComposerModel | undefined
-  const queue = createSessionQueue({
-    sessionID: requireSessionID(props.session),
-    draft: adapter.state,
-    working: adapter.working,
-    behavior: settings.general.followUpBehavior,
-    composer: () => composer,
-  })
-  composer = createComposerModel(adapter, { queue })
+export function ActiveSessionComposerRegion(props: { model: SessionComposerController }) {
  return (
    <SessionComposerRegion
-      controller={region}
+      controller={props.model.region}
      composer={
        <div class="relative">
-          <SessionQueuePanel queue={queue} />
+          <SessionQueuePanel queue={props.model.queue} />
          <div class="relative z-10">
-            <Composer model={composer} borderUnderlay />
+            <Composer model={props.model.composer} borderUnderlay />
          </div>
        </div>
      }
    />
  )
 }
-
-function requireSessionID(session: SessionModel) {
-  const id = session.identity.params.id
-  if (!id) throw new Error("Active Composer requires a Session ID")
-  return id
-}
@@ -12,8 +12,10 @@ import {
 } from "solid-js"
 import { createStore } from "solid-js/store"
 import { ResizeHandle } from "@opencode-ai/ui/resize-handle"
+import { Icon } from "@opencode-ai/ui/icon"
 import { MessageTimeline, SessionSummaryPanel } from "@/session/timeline/message-timeline"
 import { useServer } from "@/runtime/server/current"
+import { useLanguage } from "@/runtime/i18n/language"
 import { projectForSession } from "@/shell/layout/helpers"
 import type { SessionModel } from "@/session/model"
 import { SESSION_PANEL_WIDTH_MIN } from "@/session/session-panel-width"
@@ -39,6 +41,7 @@ const SessionMobileFiles = lazy(async () => {
 export function SessionScreen(props: { session: SessionModel }) {
  const session = props.session
  const server = useServer()
+  const language = useLanguage()
  const detailsProject = createMemo(() => {
    const info = session.data.info()
    return info ? projectForSession(info, server.ctx.sync.data.project) : undefined
@@ -60,6 +63,7 @@ export function SessionScreen(props: { session: SessionModel }) {
  const [elements, setElements] = createStore<{
    side?: HTMLDivElement
    bottomTerminal?: HTMLDivElement
+    dropzone?: HTMLDivElement
  }>({})
  const sideVisible = createMemo(() => isDesktop() && screen.side.layout().visible)
  const sideTerminalVisible = createMemo(() => isDesktop() && screen.terminal.side() && screen.terminal.open())
@@ -134,7 +138,20 @@ export function SessionScreen(props: { session: SessionModel }) {
    session,
    screen,
    timeline,
+    visible: conversationVisible,
  })
+  const dropLabel = createMemo(() => {
+    const input = composer.drop.input()
+    if (!input?.image && !input?.pdf) return language.t("ui.promptInput.dropFiles")
+    if (!input.pdf) return language.t("ui.promptInput.dropFiles.image")
+    if (!input.image) return language.t("ui.promptInput.dropFiles.pdf")
+    return language.t("ui.promptInput.dropFiles.imagePdf")
+  })
+  const dropPresence = createAnimatedPresence(
+    () => (composer.drop.active() ? dropLabel() : undefined),
+    () => elements.dropzone ?? null,
+    session.layout.tabKey,
+  )

  useUsageExceededDialogs()

@@ -176,7 +193,7 @@ export function SessionScreen(props: { session: SessionModel }) {
                          review.mobile.setTab("changes")
                          session.layout.view().terminal.close()
                        }}
-                        backgroundTasks={composer.region.state.background.tasks()}
+                        backgroundTasks={composer.requests.background.tasks()}
                      />
                    )}
                  </Show>
@@ -198,6 +215,63 @@ export function SessionScreen(props: { session: SessionModel }) {

  const sessionPanelContent = () => (
    <>
+      <div
+        data-slot="session-dropzone-blur"
+        data-visible={composer.drop.active()}
+        class="pointer-events-none absolute inset-0 z-[79] rounded-[inherit] opacity-[0.001] backdrop-blur-[1.5px] transition-opacity duration-200 ease-[cubic-bezier(0.215,0.61,0.355,1)] will-change-[opacity,backdrop-filter] data-[visible=true]:opacity-100 motion-reduce:transition-none"
+        style={{
+          "-webkit-mask-image":
+            "linear-gradient(to right, transparent 0%, black 25%, black 75%, transparent 100%), linear-gradient(to bottom, transparent 0%, black 28%, black 72%, transparent 100%)",
+          "-webkit-mask-composite": "source-in",
+          "mask-image":
+            "linear-gradient(to right, transparent 0%, black 25%, black 75%, transparent 100%), linear-gradient(to bottom, transparent 0%, black 28%, black 72%, transparent 100%)",
+          "mask-composite": "intersect",
+        }}
+      />
+      <Show when={dropPresence.present()}>
+        <div
+          ref={(element) => setElements("dropzone", element)}
+          data-component="session-dropzone"
+          data-visible={composer.drop.active()}
+          class="pointer-events-none absolute inset-0 z-[80] grid place-items-center overflow-hidden rounded-[inherit] bg-[color-mix(in_srgb,var(--v2-text-text-base)_var(--session-dropzone-wash),transparent)] opacity-100 transition-opacity duration-200 ease-[cubic-bezier(0.215,0.61,0.355,1)] data-[visible=false]:opacity-0 motion-reduce:transition-none"
+        >
+          <div class="absolute inset-0 bg-v2-background-bg-base/25" />
+          <div
+            class="absolute inset-y-0 left-1/2 w-full -translate-x-1/2 md:max-w-200 2xl:max-w-[1000px]"
+            style={{
+              "-webkit-mask-image": "linear-gradient(to right, transparent 0%, black 12%, black 88%, transparent 100%)",
+              "mask-image": "linear-gradient(to right, transparent 0%, black 12%, black 88%, transparent 100%)",
+            }}
+          >
+            <div
+              data-slot="session-dropzone-stripes"
+              class="absolute inset-0 opacity-60"
+              style={{
+                background:
+                  "repeating-linear-gradient(135deg, transparent 0px, transparent 12px, color-mix(in srgb, var(--v2-text-text-base) var(--session-dropzone-stripe), transparent) 12px, color-mix(in srgb, var(--v2-text-text-base) var(--session-dropzone-stripe), transparent) 24px)",
+                "-webkit-mask-image":
+                  "radial-gradient(ellipse 59% 40% at center, black 0%, rgba(0,0,0,0.72) 58%, transparent 100%)",
+                "mask-image":
+                  "radial-gradient(ellipse 59% 40% at center, black 0%, rgba(0,0,0,0.72) 58%, transparent 100%)",
+              }}
+            />
+          </div>
+          <div
+            data-slot="session-dropzone-content"
+            class="relative flex translate-y-0 flex-col items-center gap-5 opacity-100 transition-[opacity,transform] duration-200 ease-[cubic-bezier(0.215,0.61,0.355,1)] data-[visible=false]:translate-y-1 data-[visible=false]:opacity-0 motion-reduce:transition-none"
+            data-visible={composer.drop.active()}
+          >
+            <div
+              data-slot="session-dropzone-upload"
+              class="flex size-10 items-center justify-center rounded-full bg-[var(--session-dropzone-card)] text-v2-icon-icon-muted shadow-[var(--v2-elevation-floating)]"
+              aria-hidden="true"
+            >
+              <Icon name="arrow-up" size="normal" class="text-v2-icon-icon-muted" />
+            </div>
+            <div class="text-[15px] font-[530] leading-6 text-v2-text-text-base">{dropPresence.value()}</div>
+          </div>
+        </div>
+      </Show>
      <Show when={!isDesktop() && !!session.identity.params.id}>{mobileTabs()}</Show>
      {/* Surface query errors without suspending session metadata while messages load. */}
      <Show when={timeline.resource.error}>
@@ -235,7 +309,7 @@ export function SessionScreen(props: { session: SessionModel }) {
                <MessageTimeline
                  hideHeader={!isDesktop()}
                  session={session}
-                  background={composer.region.state.background}
+                  background={composer.requests.background}
                  actions={composer.actions.timeline}
                  scroll={timeline.scroll}
                  onResumeScroll={timeline.actions.resume}
@@ -263,10 +337,8 @@ export function SessionScreen(props: { session: SessionModel }) {
        </Switch>
      </div>

-      <Show when={conversationVisible() ? session.identity.params.id : undefined} keyed>
-        {(_id) => (
-          <ActiveSessionComposerRegion model={composer} session={session} onResponseSubmit={timeline.actions.resume} />
-        )}
+      <Show when={composer.active()} keyed>
+        {(model) => <ActiveSessionComposerRegion model={model} />}
      </Show>
    </>
  )
@@ -14,7 +14,7 @@ export function SessionRouteFrame(props: ParentProps<{ padded?: boolean }>) {
 export function SessionPanelFrame(props: ParentProps<{ raised?: boolean }>) {
  return (
    <div
-      class="flex min-h-0 flex-1 flex-col overflow-hidden rounded-[10px] bg-v2-background-bg-base"
+      class="relative flex min-h-0 flex-1 flex-col overflow-hidden rounded-[10px] bg-v2-background-bg-base"
      classList={{
        "shadow-[var(--v2-elevation-raised)]": props.raised,
      }}
@@ -242,7 +242,7 @@ export function SessionIdentityHeader(props: { sessionID: string; session?: Sess
  )
  const title = createMemo(() =>
    pending()
-      ? language.t("command.session.new")
+      ? language.t("session.tab.session")
      : sessionTitle(props.session?.title ?? (parentID() ? undefined : info()?.title)),
  )
  const project = createMemo(() => {
@@ -0,0 +1,36 @@
+import { expect, test } from "bun:test"
+import { render } from "solid-js/web"
+import { createComposerAttachments } from "@/composer/attachments/attachments"
+
+test("clears drag state on platform cancellation", async () => {
+  let cancel = () => {}
+  let subscribed = false
+  let dragging: "image" | "@mention" | null = "image"
+  const dispose = render(() => {
+    createComposerAttachments({
+      capture: () => ({ current: () => [], cursor: () => 0, set: () => {} }),
+      editor: () => undefined,
+      focusEditor: () => {},
+      addPart: () => false,
+      setDraggingType: (type) => (dragging = type),
+      directory: () => "",
+      isDialogActive: () => false,
+      warn: () => {},
+      duplicate: () => {},
+      onError: () => {},
+      onDragCancel: (callback) => {
+        cancel = callback
+        subscribed = true
+        return () => (subscribed = false)
+      },
+    })
+    return null
+  }, document.createElement("div"))
+  await Promise.resolve()
+
+  cancel()
+
+  expect(dragging).toBeNull()
+  dispose()
+  expect(subscribed).toBeFalse()
+})
@@ -1109,6 +1109,8 @@ export async function handler(
    authInfo = authInfo!

    const cost = centsToMicroCents(totalCostInCent)
+    // Keep period bounds and persisted timestamps on one snapshot when a queued write crosses a reset boundary.
+    const trackedAt = new Date()

    // For hot workspaces, batch balance/usage updates through Redis to avoid
    // row-level lock contention on BillingTable/UserTable. Returns the amount
@@ -1149,7 +1151,7 @@ export async function handler(
          if (billingSource === "subscription") {
            const plan = authInfo.billing.subscription!.plan
            const black = BlackData.getLimits({ plan })
-            const week = getWeekBounds(new Date())
+            const week = getWeekBounds(trackedAt)
            const rollingWindowSeconds = black.rollingWindow * 3600
            return [
              db
@@ -1157,11 +1159,17 @@ export async function handler(
                .set({
                  fixedUsage: sql`
              CASE
+                WHEN ${SubscriptionTable.timeFixedUpdated} >= ${week.end} THEN ${SubscriptionTable.fixedUsage}
                WHEN ${SubscriptionTable.timeFixedUpdated} >= ${week.start} THEN ${SubscriptionTable.fixedUsage} + ${cost}
                ELSE ${cost}
              END
            `,
-                  timeFixedUpdated: sql`now()`,
+                  timeFixedUpdated: sql`
+              CASE
+                WHEN ${SubscriptionTable.timeFixedUpdated} > ${trackedAt} THEN ${SubscriptionTable.timeFixedUpdated}
+                ELSE ${trackedAt}
+              END
+            `,
                  rollingUsage: sql`
              CASE
                WHEN UNIX_TIMESTAMP(${SubscriptionTable.timeRollingUpdated}) >= UNIX_TIMESTAMP(now()) - ${rollingWindowSeconds} THEN ${SubscriptionTable.rollingUsage} + ${cost}
@@ -1185,8 +1193,8 @@ export async function handler(
          }
          if (billingSource === "lite") {
            const lite = LiteData.getLimits()
-            const week = getWeekBounds(new Date())
-            const month = getMonthlyBounds(new Date(), authInfo.lite!.timeCreated)
+            const week = getWeekBounds(trackedAt)
+            const month = getMonthlyBounds(trackedAt, authInfo.lite!.timeCreated)
            const rollingWindowSeconds = lite.rollingWindow * 3600
            const quotaCost = Math.round(cost * modelInfo.costMultiplier)
            return [
@@ -1195,18 +1203,30 @@ export async function handler(
                .set({
                  monthlyUsage: sql`
              CASE
+                WHEN ${LiteTable.timeMonthlyUpdated} >= ${month.end} THEN ${LiteTable.monthlyUsage}
                WHEN ${LiteTable.timeMonthlyUpdated} >= ${month.start} THEN ${LiteTable.monthlyUsage} + ${quotaCost}
                ELSE ${quotaCost}
              END
            `,
-                  timeMonthlyUpdated: sql`now()`,
+                  timeMonthlyUpdated: sql`
+              CASE
+                WHEN ${LiteTable.timeMonthlyUpdated} > ${trackedAt} THEN ${LiteTable.timeMonthlyUpdated}
+                ELSE ${trackedAt}
+              END
+            `,
                  weeklyUsage: sql`
              CASE
+                WHEN ${LiteTable.timeWeeklyUpdated} >= ${week.end} THEN ${LiteTable.weeklyUsage}
                WHEN ${LiteTable.timeWeeklyUpdated} >= ${week.start} THEN ${LiteTable.weeklyUsage} + ${quotaCost}
                ELSE ${quotaCost}
              END
            `,
-                  timeWeeklyUpdated: sql`now()`,
+                  timeWeeklyUpdated: sql`
+              CASE
+                WHEN ${LiteTable.timeWeeklyUpdated} > ${trackedAt} THEN ${LiteTable.timeWeeklyUpdated}
+                ELSE ${trackedAt}
+              END
+            `,
                  rollingUsage: sql`
              CASE
                WHEN UNIX_TIMESTAMP(${LiteTable.timeRollingUpdated}) >= UNIX_TIMESTAMP(now()) - ${rollingWindowSeconds} THEN ${LiteTable.rollingUsage} + ${quotaCost}
@@ -416,8 +416,9 @@ function callOptions(
  modelID: ID,
  optionKey: string,
 ): LanguageModelV3CallOptions {
+  const flattened = ProviderShared.flattenToolRequest(request)
  return {
-    prompt: prompt(request),
+    prompt: prompt(flattened.request),
    maxOutputTokens: request.generation?.maxTokens,
    temperature: request.generation?.temperature,
    stopSequences: request.generation?.stop === undefined ? undefined : [...request.generation.stop],
@@ -426,7 +427,7 @@ function callOptions(
    presencePenalty: request.generation?.presencePenalty,
    frequencyPenalty: request.generation?.frequencyPenalty,
    seed: request.generation?.seed,
-    tools: request.tools.map(tool),
+    tools: flattened.tools.map(tool),
    toolChoice: toolChoice(request.toolChoice),
    headers: request.http?.headers,
    providerOptions: requestProviderOptions(request.providerOptions, packageName, modelID, optionKey),
@@ -1,11 +1,11 @@
 import type { IntegrationOAuthMethodRegistration } from "@opencode-ai/plugin/effect/integration"
+import type { SessionRequestKind } from "@opencode-ai/plugin/effect/session"
 import { Effect, Option, Schema, Semaphore, Stream } from "effect"
 import { Catalog } from "../../catalog.js"
 import { Credential } from "../../credential.js"
 import { Bus } from "../../bus.js"
 import { CopilotModels } from "../../github-copilot/models.js"
 import { App } from "../../app.js"
-import { Agent } from "../../agent.js"
 import { Integration } from "../../integration.js"
 import { Model } from "../../model.js"
 import { define } from "@opencode-ai/plugin/effect/plugin"
@@ -259,7 +259,7 @@ export const GithubCopilotPlugin = define({
          const session = yield* ctx.session
            .get({ sessionID: evt.sessionID })
            .pipe(Effect.orElseSucceed(() => undefined))
-          const interaction = interactionType(evt.agent, session?.parentID !== undefined)
+          const interaction = interactionType(evt.kind, session?.parentID !== undefined)
          evt.headers["X-Interaction-Type"] = interaction
          if (interaction !== "conversation-agent") evt.headers["x-initiator"] = "agent"
        }),
@@ -391,9 +391,9 @@ function applyHeaders(

 // Mirrors the Copilot client's X-Interaction-Type vocabulary: the agent loop is the default,
 // nested sessions are subagents, and title/compaction are the two utility overrides.
-export function interactionType(agent: Agent.ID, child: boolean) {
-  if (agent === Agent.ID.make("title")) return "conversation-background"
-  if (agent === Agent.ID.make("compaction")) return "conversation-compaction"
+export function interactionType(kind: SessionRequestKind, child: boolean) {
+  if (kind === "title") return "conversation-background"
+  if (kind === "compaction") return "conversation-compaction"
  if (child) return "conversation-subagent"
  return "conversation-agent"
 }
@@ -396,6 +396,7 @@ export const layer = Layer.effect(
        messages: history.messages,
      })
      const prepared = yield* input.prepare({
+        kind: "compaction",
        scope: {
          session: context.session,
          agentID: Agent.ID.make("compaction"),
@@ -38,6 +38,7 @@ export const generate = Effect.fn("SessionGenerate.generate")(function* (input:
      messages: history.messages,
    })
    const prepared = yield* context.prepare({
+      kind: "generate",
      scope: { session: selection.session, agentID: selection.agent.id, model, tools: selection.tools },
      transcript: {
        system: transcript.system,
@@ -2,6 +2,7 @@ export * as SessionModelRequest from "./model-request.js"

 import { HttpOptions, LanguageModel, LLM, LLMRequest, Message, SystemPart } from "@opencode-ai/ai"
 import type { StreamOptions } from "@opencode-ai/ai/route"
+import type { SessionRequestKind } from "@opencode-ai/plugin/effect/session"
 import type { Agent } from "@opencode-ai/schema/agent"
 import type { Model } from "@opencode-ai/schema/model"
 import type { Content } from "@opencode-ai/schema/tool"
@@ -59,6 +60,8 @@ export interface Prepared {
 }

 interface PrepareInput {
+  /** Which Session flow issues this request; request hooks receive it alongside the Session identity. */
+  readonly kind: SessionRequestKind
  readonly scope: {
    readonly session: SessionSchema.Info
    readonly agentID: Agent.ID
@@ -197,6 +200,7 @@ interface HookScope {
  readonly sessionID: SessionSchema.ID
  readonly agent: Agent.ID
  readonly model: Model.Ref
+  readonly kind: SessionRequestKind
 }

 const sessionHeaders = (session: Pick<SessionSchema.Info, "id" | "parentID" | "projectID">, app: App.Info) => ({
@@ -325,7 +329,7 @@ export const layer = Layer.effect(
      )
      const request = yield* applyModelHooks(
        hooks,
-        { sessionID: session.id, agent: input.scope.agentID, model: resolved.ref },
+        { sessionID: session.id, agent: input.scope.agentID, model: resolved.ref, kind: input.kind },
        LLM.request({
          model,
          http: {
@@ -356,6 +360,7 @@ export const layer = Layer.effect(
            sessionID: session.id,
            agent: input.scope.agentID,
            model: resolved.ref,
+            kind: input.kind,
          })
        : undefined
      const options: StreamOptions = {
@@ -217,6 +217,7 @@ const layer = Layer.effect(
          messages: loaded.messages,
        })
        const prepared = yield* context.prepare({
+          kind: "primary",
          scope: { session: loaded.session, agentID: loaded.agent.id, model: loaded.model, tools: loaded.tools },
          transcript: {
            system: transcript.system,
@@ -64,6 +64,7 @@ export const layer = Layer.effect(
          : Effect.void,
      )
      const prepared = yield* context.prepare({
+        kind: "title",
        scope: { session: input.session, agentID: input.agent.id, model: input.model },
        transcript: {
          system: input.agent.system ? [SystemPart.make(input.agent.system)] : [],
@@ -18,6 +18,7 @@ const jsonSchemas = Effect.runSync(
 )

 export const definition = (tool: Tool.Info<any, any>): ToolDefinition => ({
+  type: "tool",
  name: effectiveName(tool),
  description: tool.description,
  inputSchema: inputJsonSchema(tool.input),
@@ -281,6 +281,7 @@ describe("AzurePlugin", () => {
            sessionID: Session.ID.make("ses_azure"),
            agent: Agent.ID.make("build"),
            model,
+            kind: "primary",
            request: new Request("https://test-resource.openai.azure.com/openai/v1/responses", {
              headers: { "api-key": "stored-token", "x-keep": "yes" },
            }),
@@ -295,6 +296,7 @@ describe("AzurePlugin", () => {
            sessionID: Session.ID.make("ses_foundry"),
            agent: Agent.ID.make("build"),
            model,
+            kind: "primary",
            request: new Request("https://test-resource.services.ai.azure.com/anthropic/v1/messages", {
              headers: { "x-api-key": "stored-token" },
            }),
@@ -19,6 +19,7 @@ import {
 } from "@opencode-ai/core/plugin/provider/github-copilot"
 import { Provider } from "@opencode-ai/core/provider"
 import { Integration } from "@opencode-ai/core/integration"
+import type { SessionRequestKind } from "@opencode-ai/plugin/effect/session"
 import { fakeSelectorSdk } from "../fixture/selector"
 import { testEffect } from "../lib/effect"
 import { PluginTestLayer } from "./fixture"
@@ -44,12 +45,13 @@ const sessions = Effect.fn(function* () {
  return { parent: parent.id, child: child.id }
 })

-const modelRequest = Effect.fn(function* (sessionID: Session.ID, agent: string) {
+const modelRequest = Effect.fn(function* (sessionID: Session.ID, kind: SessionRequestKind, agent = "build") {
  const hooks = yield* PluginHooks.Service
  return yield* hooks.trigger("session", "model.request", {
    sessionID,
    agent: Agent.ID.make(agent),
    model: Model.Ref.make({ providerID: Provider.ID.githubCopilot, id: Model.ID.make("gpt-5.4") }),
+    kind,
    headers: {},
  })
 })
@@ -154,6 +156,7 @@ describe("GithubCopilotPlugin", () => {
        sessionID: Session.ID.make("ses_test"),
        agent: Agent.ID.make("build"),
        model: Model.Ref.make({ providerID: Provider.ID.githubCopilot, id: Model.ID.make("claude-sonnet-4.5") }),
+        kind: "primary",
        request: new Request("https://api.githubcopilot.com/v1/messages", {
          method: "POST",
          headers: { "Content-Type": "application/json", "x-api-key": "token" },
@@ -171,7 +174,7 @@ describe("GithubCopilotPlugin", () => {
  it.effect("classifies main-loop steps as agent interactions", () =>
    Effect.gen(function* () {
      yield* addPlugin()
-      const event = yield* modelRequest((yield* sessions()).parent, "build")
+      const event = yield* modelRequest((yield* sessions()).parent, "primary")
      expect(event.headers).toEqual({ "X-Interaction-Type": "conversation-agent" })
    }),
  )
@@ -179,7 +182,7 @@ describe("GithubCopilotPlugin", () => {
  it.effect("classifies child-session steps as subagent interactions", () =>
    Effect.gen(function* () {
      yield* addPlugin()
-      const event = yield* modelRequest((yield* sessions()).child, "build")
+      const event = yield* modelRequest((yield* sessions()).child, "primary")
      expect(event.headers).toEqual({ "X-Interaction-Type": "conversation-subagent", "x-initiator": "agent" })
    }),
  )
@@ -192,14 +195,22 @@ describe("GithubCopilotPlugin", () => {
    }),
  )

-  it.effect("classifies compaction requests", () =>
+  it.effect("classifies compaction requests by kind rather than agent", () =>
    Effect.gen(function* () {
      yield* addPlugin()
-      const event = yield* modelRequest((yield* sessions()).child, "compaction")
+      const event = yield* modelRequest((yield* sessions()).child, "compaction", "build")
      expect(event.headers).toEqual({ "X-Interaction-Type": "conversation-compaction", "x-initiator": "agent" })
    }),
  )

+  it.effect("does not classify by agent name", () =>
+    Effect.gen(function* () {
+      yield* addPlugin()
+      const event = yield* modelRequest((yield* sessions()).parent, "primary", "compaction")
+      expect(event.headers).toEqual({ "X-Interaction-Type": "conversation-agent" })
+    }),
+  )
+
  it.effect("ignores other providers' model requests", () =>
    Effect.gen(function* () {
      yield* addPlugin()
@@ -208,6 +219,7 @@ describe("GithubCopilotPlugin", () => {
        sessionID: (yield* sessions()).parent,
        agent: Agent.ID.make("build"),
        model: Model.Ref.make({ providerID: Provider.ID.make("openai"), id: Model.ID.make("gpt-5.4") }),
+        kind: "primary",
        headers: {},
      })
      expect(event.headers).toEqual({})
@@ -236,6 +248,14 @@ describe("GithubCopilotPlugin", () => {
    }),
  )

+  it.effect("classifies session generation requests as agent interactions", () =>
+    Effect.gen(function* () {
+      yield* addPlugin()
+      const event = yield* modelRequest((yield* sessions()).parent, "generate")
+      expect(event.headers).toEqual({ "X-Interaction-Type": "conversation-agent" })
+    }),
+  )
+
  it.effect("creates the bundled Copilot SDK for the GitHub Copilot package", () =>
    Effect.gen(function* () {
      const aisdk = yield* AISDK.Service
@@ -48,6 +48,7 @@ const request = Effect.fn(function* (providerID: Provider.ID, baseURL: string) {
    sessionID: Session.ID.make("ses_test"),
    agent: Agent.ID.make("build"),
    model: Model.Ref.make({ providerID, id: Model.ID.make("gpt-5.5") }),
+    kind: "primary",
    baseURL,
    headers: {},
  })
@@ -226,6 +227,7 @@ describe("OpenAIPlugin", () => {
      const program = Effect.gen(function* () {
        const requests = yield* SessionModelRequest.Service
        return yield* requests.prepare({
+          kind: "primary",
          scope: {
            session: Session.Info.make({
              id: sessionID,
@@ -0,0 +1,80 @@
+import { describe, expect } from "bun:test"
+import { OpenAIChat } from "@opencode-ai/ai/protocols"
+import { Agent } from "@opencode-ai/schema/agent"
+import { Money } from "@opencode-ai/schema/money"
+import { Session } from "@opencode-ai/schema/session"
+import type { SessionRequestKind } from "@opencode-ai/plugin/effect/session"
+import { Location } from "@opencode-ai/core/location"
+import { PluginHooks } from "@opencode-ai/core/plugin/hooks"
+import { Project } from "@opencode-ai/core/project"
+import { AbsolutePath } from "@opencode-ai/core/schema"
+import { SessionModelRequest } from "@opencode-ai/core/session/model-request"
+import { SessionModelTransport } from "@opencode-ai/core/session/model-transport"
+import { SessionRunnerModel } from "@opencode-ai/core/session/runner/model"
+import { DateTime, Effect } from "effect"
+import { HttpClientRequest, HttpClientResponse } from "effect/unstable/http"
+import { testEffect } from "./lib/effect"
+import { PluginTestLayer } from "./plugin/fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const KINDS: ReadonlyArray<SessionRequestKind> = ["primary", "compaction", "title", "generate"]
+
+const session = Session.Info.make({
+  id: Session.ID.make("ses_hook_kind"),
+  projectID: Project.ID.global,
+  cost: Money.USD.zero,
+  tokens: { input: 0, output: 0, reasoning: 0, cache: { read: 0, write: 0 } },
+  time: { created: DateTime.makeUnsafe(0), updated: DateTime.makeUnsafe(0) },
+  location: Location.Ref.make({ directory: AbsolutePath.make("/project") }),
+})
+const model = SessionRunnerModel.resolved(OpenAIChat.route.model({ id: "gpt-5.5", provider: "test" }), {
+  capabilities: { tools: true, input: ["text"], output: ["text"] },
+  cost: [],
+  limit: { context: 200_000, output: 32_000 },
+})
+const transport = SessionModelTransport.Service.of({
+  bind: () => ({ execute: () => Effect.die("unused WebSocket execution") }),
+  close: () => Effect.void,
+  closeAll: Effect.void,
+})
+
+describe("SessionModelRequest HTTP hooks", () => {
+  it.effect("tags every Session request kind on http.request and http.response", () =>
+    Effect.gen(function* () {
+      const hooks = yield* PluginHooks.Service
+      const seen: Array<{ hook: string; kind: SessionRequestKind; agent: Agent.ID }> = []
+      yield* hooks.register("session", "http.request", (event) =>
+        Effect.sync(() => {
+          seen.push({ hook: "request", kind: event.kind, agent: event.agent })
+        }),
+      )
+      yield* hooks.register("session", "http.response", (event) =>
+        Effect.sync(() => {
+          seen.push({ hook: "response", kind: event.kind, agent: event.agent })
+        }),
+      )
+      const requests = yield* SessionModelRequest.Service.pipe(Effect.provide(SessionModelRequest.layer))
+
+      for (const kind of KINDS) {
+        const prepared = yield* requests.prepare({
+          kind,
+          scope: { session, agentID: Agent.ID.make("build"), model },
+          transcript: { system: [], messages: [] },
+        })
+        const http = prepared.options.http
+        if (!http) throw new Error(`Expected HTTP middleware for ${kind}`)
+        yield* http(HttpClientRequest.post("https://example.test/v1/chat/completions"), (request) =>
+          Effect.succeed(HttpClientResponse.fromWeb(request, new Response("{}", { status: 200 }))),
+        )
+      }
+
+      expect(seen).toEqual(
+        KINDS.flatMap((kind) => [
+          { hook: "request", kind, agent: Agent.ID.make("build") },
+          { hook: "response", kind, agent: Agent.ID.make("build") },
+        ]),
+      )
+    }).pipe(Effect.provideService(SessionModelTransport.Service, transport)),
+  )
+})
@@ -27,6 +27,7 @@ test("tools are structural values", async () => {
  const tool: Info = config

  expect(definition(tool)).toEqual({
+    type: "tool",
    name: "foreign",
    description: "Foreign tool",
    inputSchema: {
@@ -142,6 +143,7 @@ test("portable schemas validate and describe typed tools", async () => {
  }

  expect(definition(tool)).toEqual({
+    type: "tool",
    name: "portable",
    description: "Portable tool",
    inputSchema: { type: "object", properties: { count: { type: "string" } } },
@@ -161,6 +163,7 @@ test("Zod schemas validate, transform, and describe typed tools", async () => {
  }

  expect(definition(tool)).toEqual({
+    type: "tool",
    name: "zod",
    description: "Zod tool",
    inputSchema: {
@@ -317,6 +320,7 @@ test("raw JSON schemas validate and decode tool input", async () => {
  }

  expect(definition(tool)).toEqual({
+    type: "tool",
    name: "raw",
    description: "Raw tool",
    inputSchema: input,
@@ -400,6 +404,7 @@ test("missing external input schemas fall back to an empty schema", () => {
  } as unknown as Info

  expect(definition(tool)).toEqual({
+    type: "tool",
    name: "external",
    description: "External tool",
    inputSchema: {},
@@ -4,7 +4,7 @@ import { app, BrowserWindow, MessageChannelMain } from "electron"
 import { Effect, Layer } from "effect"
 import { RpcServer } from "effect/unstable/rpc"
 import { DesktopRpcs } from "../shared/ipc-rpc"
-import { IpcTransportPort } from "../shared/ipc-transport"
+import { DragCancelEvent, IpcTransportPort } from "../shared/ipc-transport"
 import { DesktopFiles, openExternalURL } from "./files"
 import { appHandlers } from "./ipc-handlers/app"
 import { eventHandlers } from "./ipc-handlers/events"
@@ -59,6 +59,10 @@ export const registerIpcHandlers = Effect.gen(function* () {
    relaunch: lifecycle.relaunch,
  }
  const wire = (_event: Electron.Event, win: BrowserWindow) => {
+    win.webContents.on("before-input-event", (_event, input) => {
+      if (input.type !== "keyDown" || input.key !== "Escape") return
+      win.webContents.send(DragCancelEvent)
+    })
    win.webContents.on("did-finish-load", () => {
      if (win.isDestroyed() || win.webContents.isDestroyed()) return
      const channel = new MessageChannelMain()
@@ -1,5 +1,5 @@
 import { contextBridge, ipcRenderer, webUtils } from "electron"
-import { IpcTransportPort } from "../shared/ipc-transport"
+import { DragCancelEvent, IpcTransportPort } from "../shared/ipc-transport"
 import { windowIDFromArguments } from "../shared/window-bootstrap"

 ipcRenderer.on(IpcTransportPort, (event) => {
@@ -7,6 +7,8 @@ ipcRenderer.on(IpcTransportPort, (event) => {
  if (port) window.postMessage(IpcTransportPort, "*", [port])
 })

+ipcRenderer.on(DragCancelEvent, () => window.dispatchEvent(new Event(DragCancelEvent)))
+
 contextBridge.exposeInMainWorld("electron", {
  windowID: windowIDFromArguments(process.argv),
  getPathForFile: (file: File) => webUtils.getPathForFile(file),
@@ -7,6 +7,7 @@ import {
 import type { ElectronAPI } from "../api-types"
 import { setPinchZoomEnabled, webviewZoom } from "../window/zoom"
 import { windowFullscreen } from "../window/fullscreen"
+import { DragCancelEvent } from "../../shared/ipc-transport"
 import { createDesktopFiles } from "./files"
 import { createDesktopMenuAction } from "./menu"
 import { createDesktopNotify } from "./notifications"
@@ -53,6 +54,10 @@ export function createDesktopPlatform(
    windowFullscreen,
    getPinchZoomEnabled: () => api.getPinchZoomEnabled(),
    setPinchZoomEnabled,
+    onDragCancel: (callback) => {
+      window.addEventListener(DragCancelEvent, callback)
+      return () => window.removeEventListener(DragCancelEvent, callback)
+    },
    runDesktopMenuAction: createDesktopMenuAction(api),
    checkAppExists: async (appName) => {
      return api.checkAppExists(appName)
@@ -1 +1,2 @@
 export const IpcTransportPort = "desktop-rpc-port"
+export const DragCancelEvent = "opencode:drag-cancel"
@@ -30,10 +30,17 @@ export interface SessionContext {
  providerOptions: Record<string, unknown>
 }

+/**
+ * Why a Session request is being made. Auxiliary requests share the Session's
+ * hook identity but need to be told apart from the agent loop.
+ */
+export type SessionRequestKind = "primary" | "compaction" | "title" | "generate"
+
 export interface SessionModelRequest {
  readonly sessionID: Session.ID
  readonly agent: Agent.ID
  readonly model: Model.Ref
+  readonly kind: SessionRequestKind
  baseURL?: string
  headers: Record<string, string>
 }
@@ -42,6 +49,7 @@ export interface SessionHttpRequest {
  readonly sessionID: Session.ID
  readonly agent: Agent.ID
  readonly model: Model.Ref
+  readonly kind: SessionRequestKind
  request: Request
 }

@@ -49,6 +57,7 @@ export interface SessionHttpResponse {
  readonly sessionID: Session.ID
  readonly agent: Agent.ID
  readonly model: Model.Ref
+  readonly kind: SessionRequestKind
  readonly request: Request
  response: Response
 }
@@ -30,10 +30,17 @@ export interface SessionContext {
  providerOptions: Record<string, unknown>
 }

+/**
+ * Why a Session request is being made. Auxiliary requests share the Session's
+ * hook identity but need to be told apart from the agent loop.
+ */
+export type SessionRequestKind = "primary" | "compaction" | "title" | "generate"
+
 export interface SessionModelRequest {
  readonly sessionID: Session.ID
  readonly agent: Agent.ID
  readonly model: Model.Ref
+  readonly kind: SessionRequestKind
  baseURL?: string
  headers: Record<string, string>
 }
@@ -42,6 +49,7 @@ export interface SessionHttpRequest {
  readonly sessionID: Session.ID
  readonly agent: Agent.ID
  readonly model: Model.Ref
+  readonly kind: SessionRequestKind
  request: Request
 }

@@ -49,6 +57,7 @@ export interface SessionHttpResponse {
  readonly sessionID: Session.ID
  readonly agent: Agent.ID
  readonly model: Model.Ref
+  readonly kind: SessionRequestKind
  readonly request: Request
  response: Response
 }
@@ -528,12 +528,12 @@ export function CurrentContextToolGroup(props: {
      .join(", "),
  )
  const label = createMemo(() => {
-    const notices = props.parts.filter((part) => part.type === "notice").length
-    const title =
-      [names(), notices ? i18n.plural("ui.messagePart.context.notice", notices) : undefined]
-        .filter(Boolean)
-        .join(", ") ||
-      i18n.plural("ui.messagePart.context.thought", props.parts.filter((part) => part.type === "reasoning").length)
+    const thoughts = props.parts.filter((part) => part.type === "reasoning").length
+    if (!names() && !thoughts) {
+      const title = i18n.t("ui.messagePart.context.details")
+      return { text: title, title, before: "", after: "" }
+    }
+    const title = names() || i18n.plural("ui.messagePart.context.thought", thoughts)
    const text = i18n.t("ui.messagePart.tools.used", { tools: title })
    const index = text.indexOf(title)
    return { text, title, before: text.slice(0, index).trim(), after: text.slice(index + title.length).trim() }
@@ -99,11 +99,15 @@ export function DialogModel(props: { providerID?: string }) {
            return false
          return true
        }),
+      connected(),
    )

    if (needle) {
      return prioritizeFavorites(
-        fuzzysort.go(needle, modelOptions, { keys: ["title", "category"] }).map((item) => item.obj),
+        sortModelOptions(
+          fuzzysort.go(needle, modelOptions, { keys: ["title", "category"] }).map((item) => item.obj),
+          false,
+        ),
        favoritePriority,
      )
    }
@@ -179,15 +183,24 @@ export function prioritizeFavorites<T extends { value: { providerID: string; mod
 }

 export function sortModelOptions<
-  T extends { providerID?: string; providerName?: string; releaseDate: string | number; title: string },
->(options: T[]) {
+  T extends {
+    providerID?: string
+    providerName?: string
+    releaseDate: string | number
+    title: string
+    footer?: string
+  },
+>(options: T[], grouped = true) {
  return options.toSorted((a, b) => {
-    const provider = Number(a.providerID !== "opencode") - Number(b.providerID !== "opencode")
+    const provider = grouped ? Number(a.providerID !== "opencode") - Number(b.providerID !== "opencode") : 0
    if (provider !== 0) return provider

-    const name = (a.providerName ?? "").localeCompare(b.providerName ?? "")
+    const name = grouped ? (a.providerName ?? "").localeCompare(b.providerName ?? "") : 0
    if (name !== 0) return name

+    const free = Number(b.footer === "Free") - Number(a.footer === "Free")
+    if (free !== 0) return free
+
    const release = Number(b.releaseDate) - Number(a.releaseDate)
    if (release !== 0) return release

@@ -1,4 +1,5 @@
 import { describe, expect, test } from "bun:test"
+import { go } from "fuzzysort"
 import { prioritizeFavorites, sortModelOptions } from "../../../../src/component/dialog-model"

 describe("prioritizeFavorites", () => {
@@ -23,6 +24,20 @@ describe("prioritizeFavorites", () => {
 })

 describe("sortModelOptions", () => {
+  test.each(["browse", "search", "provider"])("orders %s results free-first, then newest-first", (mode) => {
+    const options = [
+      { providerID: "opencode", title: "Claude Haiku 3", releaseDate: 1 },
+      { providerID: "anthropic", title: "Claude Haiku 4.5", releaseDate: 2 },
+      { providerID: "anthropic", title: "Claude Haiku Free", releaseDate: 0, footer: "Free" },
+    ].map((item) => ({ ...item, providerID: mode === "provider" ? "anthropic" : item.providerID }))
+    const matches = mode === "search" ? go("haik", options, { key: "title" }).map((item) => item.obj) : options
+    expect(sortModelOptions(matches, mode === "provider").map((item) => item.title)).toEqual([
+      "Claude Haiku Free",
+      "Claude Haiku 4.5",
+      "Claude Haiku 3",
+    ])
+  })
+
  test("orders opencode models before other providers", () => {
    const sorted = sortModelOptions([
      { providerID: "openai", providerName: "OpenAI", releaseDate: 3, title: "GPT 5" },
@@ -104,6 +104,7 @@ const source = {
  "ui.messagePart.review.title": "Review your answers",
  "ui.messagePart.questions.dismissed": "Questions dismissed",
  "ui.messagePart.compaction": "Session compacted",
+  "ui.messagePart.context.details": "Details",
  "ui.messagePart.context.read.one": "{{count}} read",
  "ui.messagePart.context.read.other": "{{count}} reads",
  "ui.messagePart.context.search.one": "{{count}} search",
@@ -133,7 +134,10 @@ const source = {

  "ui.promptInput.noMatchingItems": "No matching items",
  "ui.promptInput.commands": "Commands",
-  "ui.promptInput.dropFiles": "Drop files to attach",
+  "ui.promptInput.dropFiles": "Drop files to add",
+  "ui.promptInput.dropFiles.image": "Drop images or files to add",
+  "ui.promptInput.dropFiles.pdf": "Drop PDFs or files to add",
+  "ui.promptInput.dropFiles.imagePdf": "Drop images, PDFs, or files to add",
  "ui.promptInput.removeAttachment": "Remove attachment",
  "ui.promptInput.label": "Prompt",
  "ui.promptInput.placeholder.shell": "Enter shell command…",
@@ -1104,7 +1104,8 @@ effect: (ctx) =>
  }),
 ```

-Modify model request settings and optionally scope the hook to one provider.
+Modify model request settings and optionally scope the hook to one provider. The event carries the same `kind` as
+the HTTP hooks below.

 ```ts
 effect: (ctx) =>
@@ -1119,14 +1120,18 @@ effect: (ctx) =>
 ```

 Modify native provider requests or responses. Their bodies are one-shot streams; clone or replace a body before reading
-it.
+it. Both hooks run for every request a session issues; `event.kind` is `"primary"`, `"compaction"`, `"title"`, or
+`"generate"` depending on which flow issued it.

 ```ts
 effect: (ctx) =>
  Effect.gen(function* () {
    const session = ctx.session
    yield* session.hook("http.request", (event) =>
-      Effect.sync(() => event.request.headers.set("x-session-id", event.sessionID)),
+      Effect.sync(() => {
+        event.request.headers.set("x-session-id", event.sessionID)
+        if (event.kind === "title") event.request.headers.set("x-priority", "background")
+      }),
    )
    yield* session.hook("http.response", (event) =>
      Effect.sync(() => {
@@ -1139,7 +1139,8 @@ Generation options depend on the selected protocol and model:

 #### Model request

-Modify model request settings and optionally scope the hook to one provider.
+Modify model request settings and optionally scope the hook to one provider. The event carries the same `kind`
+as the HTTP hooks below.

 ```ts
 await ctx.session.hook(
@@ -1156,9 +1157,14 @@ await ctx.session.hook(
 Modify native provider requests or responses. Their bodies are one-shot streams; clone or replace a body before reading
 it.

+Both hooks run for every request a session issues. `event.kind` says which flow issued it: `"primary"` for the agent
+loop, `"compaction"` for checkpoint summaries, `"title"` for title generation, and `"generate"` for transient
+`ctx.session.generate` calls. Use it instead of the agent ID to tell auxiliary requests apart.
+
 ```ts
 await ctx.session.hook("http.request", (event) => {
  event.request.headers.set("x-session-id", event.sessionID)
+  if (event.kind === "title") event.request.headers.set("x-priority", "background")
 })

 await ctx.session.hook("http.response", (event) => {
Author	SHA1	Message	Date
opencode-agent[bot]Brendonovich Brendan Allan	b09a74591c	fix(app): omit notices from Used summary (#47245 ) Co-authored-by: Brendonovich <14191578+Brendonovich@users.noreply.github.com> Co-authored-by: Brendan Allan <git@brendonovich.dev>	2026-09-04 09:13:00 +00:00
Brendan Allan	e8481973ce	refactor(app): make session composer ownership explicit (#47254 )	2026-09-04 09:07:47 +00:00
usrnk1	211cd73f1a	feat(desktop): update composer dropzone (#42312 )	2026-09-04 16:45:42 +08:00
opencode-agent[bot]andBrendonovich	2375e81bd6	fix(app): match optimistic session heading to tab label (#47244 ) Co-authored-by: Brendonovich <14191578+Brendonovich@users.noreply.github.com>	2026-09-04 08:07:24 +00:00
opencode-agent[bot]MrMushrooooom Jack	8352addf6c	fix(console): preserve usage reset boundaries (#44729 ) Co-authored-by: MrMushrooooom <MrMushrooooom@users.noreply.github.com> Co-authored-by: Jack <jack@anoma.ly>	2026-09-04 15:12:54 +08:00
Aiden Cline	32f89748af	feat(ai): add tool namespaces (#46548 )	2026-09-04 01:09:52 -05:00
Aiden Cline	89478b36f1	refactor(plugin): rename session request kind "session" to "primary" (#47221 )	2026-09-04 00:12:18 -05:00
Aiden Cline	46458f0753	feat(core): tag session http hooks with request kind (#47214 )	2026-09-03 23:51:26 -05:00
opencode-agent[bot]andrekram1-node	c907d2ba27	fix(tui): preserve model release ordering in search (#47183 ) Co-authored-by: rekram1-node <rekram1-node@users.noreply.github.com>	2026-09-03 23:18:09 -05:00