diff --git a/packages/core/src/models-dev.ts b/packages/core/src/models-dev.ts
index 3539060724..964e4b1ac7 100644
--- a/packages/core/src/models-dev.ts
+++ b/packages/core/src/models-dev.ts
@@ -44,10 +44,7 @@ const Cost = Schema.Struct({
   ),
 })
 
-const ReasoningEffortValue = Schema.Union([
-  Schema.Null,
-  Schema.Literals(["none", "minimal", "low", "medium", "high", "xhigh", "max", "default"]),
-])
+const ReasoningEffortValue = Schema.Union([Schema.Null, Schema.String])
 
 export const ReasoningOption = Schema.Union([
   Schema.Struct({
@@ -72,7 +69,9 @@ export const Model = Schema.Struct({
   release_date: Schema.String,
   attachment: Schema.Boolean,
   reasoning: Schema.Boolean,
-  reasoning_options: Schema.optional(Schema.Array(ReasoningOption)),
+  // models.dev is external metadata and reasoning controls are expected to evolve.
+  // Keep the fetched value opaque here; provider normalization extracts the known subset.
+  reasoning_options: Schema.optional(Schema.Unknown),
   temperature: Schema.Boolean,
   tool_call: Schema.Boolean,
   interleaved: Schema.optional(
diff --git a/packages/opencode/src/provider/provider.ts b/packages/opencode/src/provider/provider.ts
index 2084040eaa..b76ea6f9c7 100644
--- a/packages/opencode/src/provider/provider.ts
+++ b/packages/opencode/src/provider/provider.ts
@@ -1186,11 +1186,37 @@ function cost(c: ModelsDev.Model["cost"]): Model["cost"] {
   return result
 }
 
+type ReasoningOption = NonNullable<Model["reasoning_options"]>[number]
+
 function reasoningOptions(model: ModelsDev.Model): Model["reasoning_options"] {
-  return model.reasoning_options?.map((option) => {
-    if (option.type === "effort") return { ...option, values: [...option.values] }
-    return { ...option }
+  if (!Array.isArray(model.reasoning_options)) return undefined
+  const normalized = model.reasoning_options.flatMap((option) => {
+    const normalized = normalizeReasoningOption(option)
+    return normalized ? [normalized] : []
   })
+  return normalized.length > 0 || model.reasoning_options.length === 0 ? normalized : undefined
+}
+
+function normalizeReasoningOption(option: unknown): ReasoningOption | undefined {
+  if (!isRecord(option) || typeof option.type !== "string") return undefined
+  if (option.type === "effort") {
+    if (!Array.isArray(option.values)) return undefined
+    return {
+      type: "effort",
+      values: option.values.filter((value): value is string | null => value === null || typeof value === "string"),
+    }
+  }
+  if (option.type === "toggle") return { type: "toggle" }
+  if (option.type === "budget_tokens") {
+    const min = typeof option.min === "number" && Number.isFinite(option.min) ? option.min : undefined
+    const max = typeof option.max === "number" && Number.isFinite(option.max) ? option.max : undefined
+    return {
+      type: "budget_tokens",
+      ...(min === undefined ? {} : { min }),
+      ...(max === undefined ? {} : { max }),
+    }
+  }
+  return undefined
 }
 
 function fromModelsDevModel(provider: ModelsDev.Provider, model: ModelsDev.Model): Model {
diff --git a/packages/opencode/test/provider/model-status.test.ts b/packages/opencode/test/provider/model-status.test.ts
index 35a859120b..ba6f360b15 100644
--- a/packages/opencode/test/provider/model-status.test.ts
+++ b/packages/opencode/test/provider/model-status.test.ts
@@ -58,4 +58,23 @@ describe("provider model status schemas", () => {
       }).status,
     ).toBe("active")
   })
+
+  test("keeps models.dev reasoning options opaque for forward compatibility", () => {
+    expect(() =>
+      Schema.decodeUnknownSync(ModelsDev.Model)({
+        id: "test-model",
+        name: "Test Model",
+        release_date: "2026-01-01",
+        attachment: false,
+        reasoning: true,
+        reasoning_options: {
+          future: "shape",
+          values: [{ type: "new_control", values: ["turbo"] }],
+        },
+        temperature: true,
+        tool_call: true,
+        limit: { context: 128000, output: 8192 },
+      }),
+    ).not.toThrow()
+  })
 })
diff --git a/packages/opencode/test/provider/provider.test.ts b/packages/opencode/test/provider/provider.test.ts
index d29101bace..f56f1c96f3 100644
--- a/packages/opencode/test/provider/provider.test.ts
+++ b/packages/opencode/test/provider/provider.test.ts
@@ -1450,6 +1450,55 @@ test("models.dev normalization preserves reasoning options for variant generatio
   expect(model.variants!.xhigh).toEqual({ reasoningEffort: "xhigh" })
 })
 
+test("models.dev normalization ignores unknown reasoning options and passes new effort strings", () => {
+  const provider = {
+    id: "custom",
+    name: "Custom",
+    env: [],
+    npm: "@ai-sdk/openai-compatible",
+    models: {
+      reasoner: {
+        id: "reasoner",
+        name: "Reasoner",
+        reasoning: true,
+        reasoning_options: [
+          { type: "future_control", values: ["turbo"] },
+          { type: "effort", values: ["turbo", 123, null] },
+          { type: "budget_tokens", min: "1024", max: 16_000 },
+          "invalid",
+        ],
+        cost: { input: 1, output: 2 },
+        limit: { context: 128_000, output: 32_000 },
+      },
+      changed: {
+        id: "changed",
+        name: "Changed",
+        reasoning: true,
+        reasoning_options: { type: "effort", values: ["turbo"] },
+        cost: { input: 1, output: 2 },
+        limit: { context: 128_000, output: 32_000 },
+      },
+      future: {
+        id: "future",
+        name: "Future",
+        reasoning: true,
+        reasoning_options: [{ type: "future_control", values: ["turbo"] }],
+        cost: { input: 1, output: 2 },
+        limit: { context: 128_000, output: 32_000 },
+      },
+    },
+  } as unknown as ModelsDev.Provider
+
+  const models = Provider.fromModelsDevProvider(provider).models
+  expect(models.reasoner.reasoning_options).toEqual([
+    { type: "effort", values: ["turbo", null] },
+    { type: "budget_tokens", max: 16_000 },
+  ])
+  expect(models.reasoner.variants).toEqual({ turbo: { reasoningEffort: "turbo" } })
+  expect(models.changed.reasoning_options).toBeUndefined()
+  expect(models.future.reasoning_options).toBeUndefined()
+})
+
 it.instance("model variants are generated for reasoning models", () =>
   Effect.gen(function* () {
     yield* set("ANTHROPIC_API_KEY", "test-api-key")