fix(provider): derive variants from reasoning metadata (#36624)

packages/core/src/models-dev.ts

@@ -44,6 +44,21 @@ const Cost = Schema.Struct({
   ),
 })
 
+const ReasoningOption = Schema.Union([
+  Schema.Struct({
+    type: Schema.Literal("effort"),
+    values: Schema.Array(Schema.NullOr(Schema.String)),
+  }),
+  Schema.Struct({
+    type: Schema.Literal("toggle"),
+  }),
+  Schema.Struct({
+    type: Schema.Literal("budget_tokens"),
+    min: Schema.optional(Schema.Finite),
+    max: Schema.optional(Schema.Finite),
+  }),
+])
+
 export const Model = Schema.Struct({
   id: Schema.String,
   name: Schema.String,
@@ -51,11 +66,9 @@ export const Model = Schema.Struct({
   release_date: Schema.String,
   attachment: Schema.Boolean,
   reasoning: Schema.Boolean,
-  // models.dev is external metadata and reasoning controls are expected to evolve.
-  // Provider normalization extracts the subset understood by this client.
-  reasoning_options: Schema.optional(Schema.Unknown),
   temperature: Schema.Boolean,
   tool_call: Schema.Boolean,
+  reasoning_options: Schema.optional(Schema.Array(ReasoningOption)),
   interleaved: Schema.optional(
     Schema.Union([
       Schema.Literal(true),

packages/core/test/models.test.ts

@@ -1,5 +1,5 @@
-import { describe, expect, beforeAll, beforeEach, afterAll, test } from "bun:test"
-import { Effect, Layer, Ref, Schema } from "effect"
+import { describe, expect, beforeAll, beforeEach, afterAll } from "bun:test"
+import { Effect, Layer, Ref } from "effect"
 import { HttpClient, HttpClientResponse } from "effect/unstable/http"
 import { AppNodeBuilder } from "@opencode-ai/core/effect/app-node-builder"
 import { LayerNodePlatform } from "@opencode-ai/core/effect/app-node-platform"
@@ -126,21 +126,6 @@ const initialState: MockState = {
   calls: [],
 }
 
-test("models.dev model schema keeps reasoning options permissive", () => {
-  const model = Schema.decodeUnknownSync(ModelsDev.Model)({
-    id: "acme-1",
-    name: "Acme One",
-    release_date: "2026-01-01",
-    attachment: false,
-    reasoning: true,
-    reasoning_options: [{ type: "future_control", value: { nested: true } }, "future-shape"],
-    temperature: true,
-    tool_call: true,
-    limit: { context: 128000, output: 8192 },
-  })
-  expect(model.reasoning_options).toEqual([{ type: "future_control", value: { nested: true } }, "future-shape"])
-})
-
 describe("ModelsDev Service", () => {
   it.live("get() returns providers from disk when cache file exists", () =>
     Effect.gen(function* () {