diff --git a/packages/openai-adapters/src/apis/Azure.ts b/packages/openai-adapters/src/apis/Azure.ts
index 4d161c8438a..a4f4203d621 100644
--- a/packages/openai-adapters/src/apis/Azure.ts
+++ b/packages/openai-adapters/src/apis/Azure.ts
@@ -35,6 +35,10 @@ export class AzureApi extends OpenAIApi {
     return apiType === "azure-openai" || apiType === "azure";
   }
 
+  private _isAzureFoundry(apiType?: string): boolean {
+    return apiType === "azure-foundry";
+  }
+
   private _getAzureBaseURL(config: z.infer<typeof AzureConfigSchema>): {
     baseURL: string;
     defaultQuery: Record<string, string>;
@@ -50,6 +54,17 @@ export class AzureApi extends OpenAIApi {
     url.pathname = url.pathname.replace(/\/$/, ""); // Remove trailing slash if present
     url.search = ""; // Clear original search params
 
+    // Azure AI Foundry (a.k.a. Microsoft Foundry / Azure serverless) uses an
+    // OpenAI-compatible routing path (`/openai/v1/...`) that the user supplies
+    // in apiBase. We must NOT append `/openai/deployments/{deployment}` like the
+    // legacy Azure OpenAI Service path — doing so 404s on Foundry endpoints.
+    if (this._isAzureFoundry(config.env?.apiType)) {
+      return {
+        baseURL: url.toString(),
+        defaultQuery: queryParams,
+      };
+    }
+
     // Default is `azure-openai` in docs, but previously was `azure`
     if (this._isAzureOpenAI(config.env?.apiType)) {
       if (!config.env?.deployment) {
diff --git a/packages/openai-adapters/src/test/main.test.ts b/packages/openai-adapters/src/test/main.test.ts
index 8a10c8b727f..a64f177288a 100644
--- a/packages/openai-adapters/src/test/main.test.ts
+++ b/packages/openai-adapters/src/test/main.test.ts
@@ -330,6 +330,38 @@ describe("Configuration", () => {
     expect((azure as OpenAIApi).openai.apiKey).toBe("sk-xxx");
   });
 
+  it("should configure Azure AI Foundry client without appending /openai/deployments/{deployment}", () => {
+    const azure = constructLlmApi({
+      provider: "azure",
+      apiKey: "sk-xxx",
+      apiBase: "https://my-resource.services.ai.azure.com/openai/v1",
+      env: {
+        apiType: "azure-foundry",
+      },
+    });
+
+    // Azure AI Foundry endpoints use the apiBase as-is (OpenAI-compatible
+    // routing path supplied by the user). Appending /openai/deployments/{deployment}
+    // would 404 because Foundry does not expose that legacy path.
+    expect((azure as OpenAIApi).openai.baseURL).toBe(
+      "https://my-resource.services.ai.azure.com/openai/v1",
+    );
+    expect((azure as OpenAIApi).openai.apiKey).toBe("sk-xxx");
+  });
+
+  it("should not require env.deployment or env.apiVersion for Azure AI Foundry", () => {
+    expect(() =>
+      constructLlmApi({
+        provider: "azure",
+        apiKey: "sk-xxx",
+        apiBase: "https://my-resource.services.ai.azure.com/openai/v1",
+        env: {
+          apiType: "azure-foundry",
+        },
+      }),
+    ).not.toThrow();
+  });
+
   describe("ollama api base", () => {
     it('should have correct default API base for "ollama"', () => {
       const ollama = constructLlmApi({