diff --git a/packages/core/src/plugin/provider/cloudflare-ai-gateway.ts b/packages/core/src/plugin/provider/cloudflare-ai-gateway.ts
index 2803cb7a8e8f..0cf10dfe6824 100644
--- a/packages/core/src/plugin/provider/cloudflare-ai-gateway.ts
+++ b/packages/core/src/plugin/provider/cloudflare-ai-gateway.ts
@@ -33,7 +33,7 @@ export const CloudflareAIGatewayPlugin = define({
             // gateway's stored/BYOK keys instead.
             const isWorkersAi = modelID.startsWith("workers-ai/") || modelID.startsWith("@cf/")
             const unified = createUnified(isWorkersAi ? { apiKey: config.apiKey } : {})
-            return gateway(unified(modelID))
+            return gateway(unified(nativeModelId(modelID)))
           },
         }
       }),
@@ -85,3 +85,15 @@ function gatewayOptions(options: Record<string, unknown>, metadata: unknown) {
 function stringOption(options: Record<string, unknown>, key: string) {
   return typeof options[key] === "string" ? options[key] : undefined
 }
+
+// models.dev publishes Anthropic ids with dot-separated version numbers (e.g.
+// "claude-haiku-4.5") to match its site-wide display convention, but Anthropic's
+// real API model slugs use dashes ("claude-haiku-4-5"). The gateway's Unified API
+// forwards the model id straight through to the upstream provider, so an
+// unmodified dotted id 404s against Anthropic with a "model not found" error.
+// Every other proxied provider in the catalog (OpenAI, xAI, Google, ...) already
+// uses dots natively, so this translation is scoped to the "anthropic/" prefix.
+function nativeModelId(modelID: string): string {
+  if (!modelID.startsWith("anthropic/")) return modelID
+  return modelID.replaceAll(".", "-")
+}
diff --git a/packages/core/test/plugin/provider-cloudflare-ai-gateway.test.ts b/packages/core/test/plugin/provider-cloudflare-ai-gateway.test.ts
index 008b9a46a3e0..7b2f21099ba1 100644
--- a/packages/core/test/plugin/provider-cloudflare-ai-gateway.test.ts
+++ b/packages/core/test/plugin/provider-cloudflare-ai-gateway.test.ts
@@ -401,6 +401,61 @@ describe("CloudflareAIGatewayPlugin", () => {
     ),
   )
 
+  it.effect("translates models.dev's dotted Anthropic ids to Anthropic's native dashed slugs", () =>
+    withEnv(cloudflareEnv(), () =>
+      Effect.gen(function* () {
+        resetCalls()
+        const plugin = yield* PluginV2.Service
+        const aisdk = yield* AISDK.Service
+        yield* addPlugin()
+
+        const result = yield* aisdk.runSDK({
+          model: ModelV2.Info.make({
+            ...ModelV2.Info.empty(
+              ProviderV2.ID.make("cloudflare-ai-gateway"),
+              ModelV2.ID.make("anthropic/claude-haiku-4.5"),
+            ),
+            api: {
+              id: ModelV2.ID.make("anthropic/claude-haiku-4.5"),
+              type: "aisdk",
+              package: "test-provider",
+            },
+          }),
+          package: "ai-gateway-provider",
+          options: { name: "cloudflare-ai-gateway" },
+        })
+
+        result.sdk.languageModel("anthropic/claude-haiku-4.5")
+
+        expect(unifiedCalls).toEqual(["anthropic/claude-haiku-4-5"])
+      }),
+    ),
+  )
+
+  it.effect("leaves non-Anthropic ids with dots untouched (e.g. OpenAI's gpt-4.1)", () =>
+    withEnv(cloudflareEnv(), () =>
+      Effect.gen(function* () {
+        resetCalls()
+        const plugin = yield* PluginV2.Service
+        const aisdk = yield* AISDK.Service
+        yield* addPlugin()
+
+        const result = yield* aisdk.runSDK({
+          model: ModelV2.Info.make({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-4.1")),
+            api: { id: ModelV2.ID.make("openai/gpt-4.1"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "ai-gateway-provider",
+          options: { name: "cloudflare-ai-gateway" },
+        })
+
+        result.sdk.languageModel("openai/gpt-4.1")
+
+        expect(unifiedCalls).toEqual(["openai/gpt-4.1"])
+      }),
+    ),
+  )
+
   it.effect("ignores non Cloudflare AI Gateway packages", () =>
     withEnv(cloudflareEnv(), () =>
       Effect.gen(function* () {