Allow SurfMind Chrome extension MCP origin (#513)

src/server/mcp/transport-v2.test.ts

@@ -9,13 +9,18 @@ const ctx: ExecutionContext = {
   props: {},
 };
 
-function request(method: string, body?: unknown) {
+function request(
+  method: string,
+  body?: unknown,
+  headers?: Record<string, string>,
+) {
   return new Request("https://open-seo.test/mcp", {
     method,
     headers: {
       Host: "open-seo.test",
       Accept: "application/json, text/event-stream",
       "Content-Type": "application/json",
+      ...headers,
     },
     body: body === undefined ? undefined : JSON.stringify(body),
   });
@@ -97,4 +102,38 @@ describe("Agents SDK v2 MCP transport", () => {
     expect(responseText).toContain('\\"scopes\\":[\\"mcp\\"]');
     expect(responseText).toContain('\\"organizationId\\":\\"org-1\\"');
   });
+
+  it("accepts the SurfMind extension origin and rejects other browser origins", async () => {
+    const handler = createMcpHandler(
+      () => new McpServer({ name: "test", version: "1.0.0" }),
+      {
+        route: "/mcp",
+        allowedOriginHostnames: [
+          "open-seo.test",
+          "pghallcbnfabbgfijhbcldaapmgidnaa",
+        ],
+      },
+    );
+    const body = {
+      jsonrpc: "2.0",
+      id: 1,
+      method: "tools/list",
+    };
+
+    const surfMindResponse = await handler(
+      request("POST", body, {
+        Origin: "chrome-extension://pghallcbnfabbgfijhbcldaapmgidnaa",
+      }),
+      {},
+      ctx,
+    );
+    const unrelatedOriginResponse = await handler(
+      request("POST", body, { Origin: "https://evil.com" }),
+      {},
+      ctx,
+    );
+
+    expect(surfMindResponse.status).toBe(200);
+    expect(unrelatedOriginResponse.status).toBe(403);
+  });
 });

src/server/mcp/transport.test.ts

@@ -215,7 +215,10 @@ describe("handleAuthenticatedOpenSeoMcpRequest", () => {
     expect(response.headers.get("connection")).not.toBe("keep-alive");
     expect(selfHostedAuthMocks.createMcpHandler).toHaveBeenCalledWith(
       expect.objectContaining({
-        allowedOriginHostnames: ["open-seo.test"],
+        allowedOriginHostnames: [
+          "open-seo.test",
+          "pghallcbnfabbgfijhbcldaapmgidnaa",
+        ],
         legacy: "reject",
       }),
     );
@@ -255,6 +258,24 @@ describe("handleAuthenticatedOpenSeoMcpRequest", () => {
     expect(selfHostedAuthMocks.createOpenSeoMcpServer).not.toHaveBeenCalled();
   });
 
+  it("accepts a legacy request from the SurfMind Chrome extension", async () => {
+    const props = hostedProps();
+
+    const response = await handleAuthenticatedOpenSeoMcpRequest(
+      createMcpRequest({
+        Origin: "chrome-extension://pghallcbnfabbgfijhbcldaapmgidnaa",
+      }),
+      props,
+      {},
+      { ...ctx, props },
+    );
+
+    expect(response.status).toBe(200);
+    expect(selfHostedAuthMocks.createOpenSeoMcpServer).toHaveBeenCalledWith(
+      props,
+    );
+  });
+
   it("rejects provider props missing the OAuth client identity", async () => {
     // Hosted tokens always carry clientId/scopes; a token without them must
     // fail closed rather than skip scope enforcement.

src/server/mcp/transport.ts

@@ -32,6 +32,8 @@ const MCP_CORS_HEADERS = {
   "Access-Control-Max-Age": "86400",
 } as const;
 
+const SURFMIND_CHROME_EXTENSION_HOSTNAME = "pghallcbnfabbgfijhbcldaapmgidnaa";
+
 function withMcpCors(response: Response) {
   const headers = new Headers(response.headers);
   for (const [name, value] of Object.entries(MCP_CORS_HEADERS)) {
@@ -158,6 +160,7 @@ export async function handleAuthenticatedOpenSeoMcpRequest(
 
   return createRequestHandler(result.data, [
     new URL(getHostedBaseUrl()).hostname,
+    SURFMIND_CHROME_EXTENSION_HOSTNAME,
   ])(request, env, ctx);
 }