diff --git a/packages/opencode/src/provider/provider.ts b/packages/opencode/src/provider/provider.ts
index 349073197d7..926ae3e1346 100644
--- a/packages/opencode/src/provider/provider.ts
+++ b/packages/opencode/src/provider/provider.ts
@@ -756,6 +756,39 @@ export namespace Provider {
     })
   export type Info = z.infer<typeof Info>
 
+  const BEDROCK_1M_MODELS = ["claude-opus-4-6", "claude-sonnet-4-5", "claude-sonnet-4-6"]
+  const BEDROCK_1M_BETA = "context-1m-2025-08-07"
+
+  function splitBedrock1m(providerID: string, models: Record<string, Model>) {
+    if (providerID !== "amazon-bedrock") return
+
+    for (const [id, model] of Object.entries(models)) {
+      if (!BEDROCK_1M_MODELS.some((m) => model.api.id.includes(m))) continue
+      if (id.endsWith("-1m")) continue
+
+      const name = model.name.replace(/\s+\((200K|1M Experimental)\)$/i, "")
+      const opts = { ...model.options }
+      const raw = opts["anthropicBeta"]
+      const existing = (Array.isArray(raw) ? raw : typeof raw === "string" ? [raw] : []).filter(
+        (item): item is string => typeof item === "string",
+      )
+      delete opts["anthropicBeta"]
+
+      model.name = `${name} (200K)`
+      model.options = opts
+      model.limit = { ...model.limit, context: Math.min(model.limit.context, 200_000) }
+
+      models[`${id}-1m`] = {
+        ...model,
+        id: ModelID.make(`${id}-1m`),
+        name: `${name} (1M Experimental)`,
+        status: "beta",
+        limit: { ...model.limit, context: 1_000_000 },
+        options: { ...model.options, anthropicBeta: [...new Set([...existing, BEDROCK_1M_BETA])] },
+      }
+    }
+  }
+
   function fromModelsDevModel(provider: ModelsDev.Provider, model: ModelsDev.Model): Model {
     const m: Model = {
       id: ModelID.make(model.id),
@@ -824,13 +857,16 @@ export namespace Provider {
   }
 
   export function fromModelsDevProvider(provider: ModelsDev.Provider): Info {
+    const models = mapValues(provider.models, (model) => fromModelsDevModel(provider, model))
+    splitBedrock1m(provider.id, models)
+
     return {
       id: ProviderID.make(provider.id),
       source: "custom",
       name: provider.name,
       env: provider.env ?? [],
       options: {},
-      models: mapValues(provider.models, (model) => fromModelsDevModel(provider, model)),
+      models,
     }
   }
 
diff --git a/packages/opencode/test/provider/provider.test.ts b/packages/opencode/test/provider/provider.test.ts
index b14d2752240..a0600134591 100644
--- a/packages/opencode/test/provider/provider.test.ts
+++ b/packages/opencode/test/provider/provider.test.ts
@@ -1410,6 +1410,211 @@ test("model headers are preserved", async () => {
   })
 })
 
+test("fromModelsDevProvider splits bedrock opus 4.6 into 200K and 1M variants", () => {
+  const provider = Provider.fromModelsDevProvider({
+    id: "amazon-bedrock",
+    name: "Amazon Bedrock",
+    env: [],
+    models: {
+      "us.anthropic.claude-opus-4-6-v1:0": {
+        id: "us.anthropic.claude-opus-4-6-v1:0",
+        name: "Claude Opus 4.6",
+        attachment: true,
+        reasoning: true,
+        tool_call: true,
+        temperature: true,
+        release_date: "2026-02-05",
+        limit: { context: 1_000_000, output: 128_000 },
+        options: {
+          anthropicBeta: ["existing-beta"],
+        },
+      },
+    },
+  })
+
+  const base = provider.models["us.anthropic.claude-opus-4-6-v1:0"]
+  const extended = provider.models["us.anthropic.claude-opus-4-6-v1:0-1m"]
+
+  expect(base).toBeDefined()
+  expect(extended).toBeDefined()
+
+  expect(base.name).toContain("(200K)")
+  expect(extended.name).toContain("(1M Experimental)")
+
+  expect(base.limit.context).toBe(200_000)
+  expect(extended.limit.context).toBe(1_000_000)
+
+  expect(base.options.anthropicBeta).toBeUndefined()
+  expect(extended.options.anthropicBeta).toEqual(expect.arrayContaining(["existing-beta", "context-1m-2025-08-07"]))
+
+  expect(extended.api.id).toBe(base.api.id)
+  expect(extended.status).toBe("beta")
+})
+
+test("fromModelsDevProvider splits bedrock sonnet 4.5 into 200K and 1M variants", () => {
+  const provider = Provider.fromModelsDevProvider({
+    id: "amazon-bedrock",
+    name: "Amazon Bedrock",
+    env: [],
+    models: {
+      "us.anthropic.claude-sonnet-4-5-20250929-v1:0": {
+        id: "us.anthropic.claude-sonnet-4-5-20250929-v1:0",
+        name: "Claude Sonnet 4.5",
+        attachment: true,
+        reasoning: true,
+        tool_call: true,
+        temperature: true,
+        release_date: "2025-09-29",
+        limit: { context: 1_000_000, output: 64_000 },
+        options: {},
+      },
+    },
+  })
+
+  const base = provider.models["us.anthropic.claude-sonnet-4-5-20250929-v1:0"]
+  const extended = provider.models["us.anthropic.claude-sonnet-4-5-20250929-v1:0-1m"]
+
+  expect(base).toBeDefined()
+  expect(extended).toBeDefined()
+
+  expect(base.name).toContain("(200K)")
+  expect(extended.name).toContain("(1M Experimental)")
+
+  expect(base.limit.context).toBe(200_000)
+  expect(extended.limit.context).toBe(1_000_000)
+
+  expect(extended.options.anthropicBeta).toEqual(["context-1m-2025-08-07"])
+  expect(extended.status).toBe("beta")
+})
+
+test("fromModelsDevProvider splits bedrock sonnet 4.6 into 200K and 1M variants", () => {
+  const provider = Provider.fromModelsDevProvider({
+    id: "amazon-bedrock",
+    name: "Amazon Bedrock",
+    env: [],
+    models: {
+      "us.anthropic.claude-sonnet-4-6-v1:0": {
+        id: "us.anthropic.claude-sonnet-4-6-v1:0",
+        name: "Claude Sonnet 4.6",
+        attachment: true,
+        reasoning: true,
+        tool_call: true,
+        temperature: true,
+        release_date: "2026-02-17",
+        limit: { context: 1_000_000, output: 64_000 },
+        options: {},
+      },
+    },
+  })
+
+  const base = provider.models["us.anthropic.claude-sonnet-4-6-v1:0"]
+  const extended = provider.models["us.anthropic.claude-sonnet-4-6-v1:0-1m"]
+
+  expect(base).toBeDefined()
+  expect(extended).toBeDefined()
+
+  expect(base.name).toContain("(200K)")
+  expect(extended.name).toContain("(1M Experimental)")
+
+  expect(base.limit.context).toBe(200_000)
+  expect(extended.limit.context).toBe(1_000_000)
+
+  expect(extended.options.anthropicBeta).toEqual(["context-1m-2025-08-07"])
+  expect(extended.status).toBe("beta")
+})
+
+test("bedrock custom opus 4.6 model is not auto-split", async () => {
+  await using tmp = await tmpdir({
+    init: async (dir) => {
+      await Bun.write(
+        path.join(dir, "opencode.json"),
+        JSON.stringify({
+          $schema: "https://opencode.ai/config.json",
+          provider: {
+            "amazon-bedrock": {
+              models: {
+                "anthropic.claude-opus-4-6-v1:0": {
+                  name: "Claude Opus 4.6",
+                  attachment: true,
+                  reasoning: true,
+                  tool_call: true,
+                  temperature: true,
+                  limit: { context: 1_000_000, output: 64_000 },
+                },
+              },
+            },
+          },
+        }),
+      )
+    },
+  })
+
+  await Instance.provide({
+    directory: tmp.path,
+    fn: async () => {
+      const providers = await Provider.list()
+      const base = providers["amazon-bedrock"].models["anthropic.claude-opus-4-6-v1:0"]
+      const extended = providers["amazon-bedrock"].models["anthropic.claude-opus-4-6-v1:0-1m"]
+
+      expect(base).toBeDefined()
+      expect(extended).toBeUndefined()
+      expect(base.name).toBe("Claude Opus 4.6")
+      expect(base.limit.context).toBe(1_000_000)
+      expect(base.options.anthropicBeta).toBeUndefined()
+    },
+  })
+})
+
+test("fromModelsDevProvider does not split non-1m bedrock models", () => {
+  const provider = Provider.fromModelsDevProvider({
+    id: "amazon-bedrock",
+    name: "Amazon Bedrock",
+    env: [],
+    models: {
+      "us.anthropic.claude-haiku-4-20250414-v1:0": {
+        id: "us.anthropic.claude-haiku-4-20250414-v1:0",
+        name: "Claude Haiku 4",
+        attachment: true,
+        reasoning: false,
+        tool_call: true,
+        temperature: true,
+        release_date: "2025-04-14",
+        limit: { context: 200_000, output: 64_000 },
+        options: {},
+      },
+    },
+  })
+
+  const models = Object.keys(provider.models)
+  expect(models).toEqual(["us.anthropic.claude-haiku-4-20250414-v1:0"])
+  expect(provider.models["us.anthropic.claude-haiku-4-20250414-v1:0-1m"]).toBeUndefined()
+})
+
+test("fromModelsDevProvider does not split non-bedrock providers", () => {
+  const provider = Provider.fromModelsDevProvider({
+    id: "anthropic",
+    name: "Anthropic",
+    env: ["ANTHROPIC_API_KEY"],
+    models: {
+      "claude-opus-4-6": {
+        id: "claude-opus-4-6",
+        name: "Claude Opus 4.6",
+        attachment: true,
+        reasoning: true,
+        tool_call: true,
+        temperature: true,
+        release_date: "2026-02-05",
+        limit: { context: 200_000, output: 128_000 },
+        options: {},
+      },
+    },
+  })
+
+  const models = Object.keys(provider.models)
+  expect(models).toEqual(["claude-opus-4-6"])
+  expect(provider.models["claude-opus-4-6-1m"]).toBeUndefined()
+})
+
 test("provider env fallback - second env var used if first missing", async () => {
   await using tmp = await tmpdir({
     init: async (dir) => {