fix(core): exclude non-text models from catalog and skip initial auto-compaction

packages/core/src/model-resolver.ts

@@ -408,7 +408,9 @@ export const layer = Layer.effect(
                 Effect.flatMap((model) =>
                   model && hasPackage(model)
                     ? Effect.succeed(model)
-                    : Effect.map(models.available(), (models) => models.find(hasPackage)),
+                    : Effect.map(models.available(), (models) =>
+                        models.find((model) => hasPackage(model) && Model.supportsText(model)),
+                      ),
                 ),
               )
         if (!selected) return undefined

packages/core/src/model.ts

@@ -261,7 +261,7 @@ const layer = Layer.effect(
         const value = yield* read()
         const requested = value.data.defaultModel
         const model = requested && value.byProvider.get(requested.providerID)?.get(requested.modelID)
-        return model?.enabled ? model : value.available[0]
+        return model?.enabled ? model : value.available.find(supportsText)
       }),
       small: Effect.fn("Model.small")(function* (providerID) {
         const value = yield* read()
@@ -282,6 +282,13 @@ const layer = Layer.effect(
 
 export const node = makeLocationNode({ service: Service, layer, deps: [Provider.node, Bus.node, Location.node] })
 
+export function supportsText(model: Pick<Info, "capabilities">) {
+  return (
+    (model.capabilities.input.length === 0 || model.capabilities.input.some((item) => item.startsWith("text"))) &&
+    (model.capabilities.output.length === 0 || model.capabilities.output.some((item) => item.startsWith("text")))
+  )
+}
+
 export function compatibility(input: unknown): Compatibility | undefined {
   if (typeof input === "string") return { reasoningField: input }
   if (typeof input !== "object" || input === null || Array.isArray(input) || !("field" in input)) return undefined

packages/core/src/plugin/models-dev.ts

@@ -3,6 +3,7 @@ import { Integration } from "@opencode/schema/integration"
 import { Provider } from "@opencode/schema/provider"
 import { Effect, Stream } from "effect"
 import { Bus } from "../bus.js"
+import { Model } from "../model.js"
 import { ModelsDev } from "../models-dev.js"
 
 // These catalog entries require inference profiles on Bedrock Runtime.
@@ -100,6 +101,7 @@ function snapshots(data: readonly ModelsDev.Snapshot[]) {
       models: provider.models.filter(
         (model) =>
           model.status !== "deprecated" &&
+          Model.supportsText(model) &&
           !(
             provider.info.id === Provider.ID.amazonBedrock &&
             BEDROCK_PROFILE_ONLY_IDS.includes(model.modelID ?? model.id)

packages/core/src/session/compaction.ts

@@ -244,6 +244,7 @@ export const layer = Layer.effect(
       // A compaction just completed; let the runner rebuild the request from it first.
       const last = messages.at(-1)
       if (last?.type === "compaction" && last.status === "completed") return false
+      if (!previousCompaction(messages) && !messages.some((message) => message.type === "assistant")) return false
       // An encrypted native window estimates as nothing, so wait for a response to measure it.
       const measured = messages.findLastIndex((message) => hasMeasuredPrompt(message, context.model.ref))
       if (measured < messages.findLastIndex(SessionProviderContext.isCheckpoint)) return false

packages/core/test/catalog.test.ts

@@ -553,6 +553,16 @@ describe("Provider and Model", () => {
         editor.models.update(providerID, Model.ID.make("new"), (model) => {
           model.time.released = 2000
         })
+        editor.models.update(providerID, Model.ID.make("newest-video"), (model) => {
+          model.capabilities.input = ["text", "image"]
+          model.capabilities.output = ["video"]
+          model.time.released = 3000
+        })
+        editor.models.update(providerID, Model.ID.make("newest-stt"), (model) => {
+          model.capabilities.input = ["audio"]
+          model.capabilities.output = ["text"]
+          model.time.released = 4000
+        })
       })
 
       expect((yield* models.default())?.id).toMatch("new")

packages/core/test/plugin/models-dev.test.ts

@@ -624,7 +624,7 @@ describe("ModelsDevPlugin", () => {
     }),
   )
 
-  it.effect("omits deprecated model definitions", () =>
+  it.effect("omits deprecated and non-text model definitions", () =>
     Effect.gen(function* () {
       const integrations = yield* Integration.Service
       const providers = yield* Provider.Service
@@ -632,11 +632,13 @@ describe("ModelsDevPlugin", () => {
       const providerID = Provider.ID.make("acme")
       const activeID = Model.ID.make("current")
       const deprecatedID = Model.ID.make("legacy")
+      const videoID = Model.ID.make("video-gen")
+      const sttID = Model.ID.make("transcribe")
       const model = {
         modelID: activeID,
         providerID,
         name: "Current",
-        capabilities: { tools: true, input: [], output: [] },
+        capabilities: { tools: true, input: ["text", "image"], output: ["text"] },
         variants: [],
         time: { released: Date.parse("2026-01-01") },
         cost: [],
@@ -662,6 +664,21 @@ describe("ModelsDevPlugin", () => {
               name: "Legacy",
               status: "deprecated" as const,
             },
+            {
+              id: videoID,
+              ...model,
+              modelID: videoID,
+              name: "Video Gen",
+              capabilities: { tools: false, input: ["text", "image"], output: ["video"] },
+              limit: { context: 1_024, output: 0 },
+            },
+            {
+              id: sttID,
+              ...model,
+              modelID: sttID,
+              name: "Transcribe",
+              capabilities: { tools: false, input: ["audio"], output: ["text"] },
+            },
           ],
         },
       ] satisfies readonly ModelsDev.Snapshot[]
@@ -684,6 +701,8 @@ describe("ModelsDevPlugin", () => {
       yield* activate(providers)
       expect(yield* modelState.get(providerID, activeID)).toBeDefined()
       expect(yield* modelState.get(providerID, deprecatedID)).toBeUndefined()
+      expect(yield* modelState.get(providerID, videoID)).toBeUndefined()
+      expect(yield* modelState.get(providerID, sttID)).toBeUndefined()
     }),
   )
 

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

@@ -3220,6 +3220,16 @@ describe("SessionRunnerLLM", () => {
     expect(yield* s.context).not.toContainEqual(expect.objectContaining({ type: "compaction" }))
   })
 
+  scenario("does not auto-compact the initial prompt before any assistant response", function* (s) {
+    s.currentModel = compactModel
+    yield* s.llm.push(TestLLM.text("Direct answer", "text-initial-over-ceiling"))
+    yield* s.runPrompt("Initial oversized request ".repeat(200))
+
+    expect(s.requests).toHaveLength(1)
+    expect(userTexts(s.requests[0])).toEqual(["Initial oversized request ".repeat(200)])
+    expect(yield* s.context).not.toContainEqual(expect.objectContaining({ type: "compaction" }))
+  })
+
   scenario("stops after required automatic compaction fails", function* (s) {
     yield* s.llm.push(TestLLM.textWithUsage("Earlier answer", "text-before-failed-compaction", 3_950))
     yield* s.runPrompt("Earlier question ".repeat(180))