feat: route browser telemetry directly to the VM by default

examples/browser-telemetry.ts

@@ -0,0 +1,30 @@
+import Kernel from '@onkernel/sdk';
+
+async function main() {
+  const kernel = new Kernel();
+
+  // Create a browser with telemetry enabled so it emits events while it runs.
+  const browser = await kernel.browsers.create({ telemetry: { enabled: true } });
+
+  try {
+    // Telemetry is a default routing subresource, so the stream goes directly to the VM automatically.
+    const stream = await kernel.browsers.telemetry.stream(browser.session_id);
+
+    // Make browser activity to generate telemetry. The "api" category emits an event per VM API call,
+    // so events arrive within ~1s.
+    for (let i = 0; i < 3; i++) {
+      await kernel.browsers.curl(browser.session_id, { url: 'https://example.com', method: 'GET' });
+    }
+
+    // Print a few events, then stop so the program terminates promptly.
+    let count = 0;
+    for await (const event of stream) {
+      console.log('telemetry event', event);
+      if (++count >= 3) break;
+    }
+  } finally {
+    await kernel.browsers.deleteByID(browser.session_id);
+  }
+}
+
+void main();

src/lib/browser-routing.ts

@@ -28,7 +28,7 @@ export class BrowserRouteCache {
 }
 
 const BROWSER_ROUTING_SUBRESOURCES_ENV = 'KERNEL_BROWSER_ROUTING_SUBRESOURCES';
-const DEFAULT_BROWSER_ROUTING_SUBRESOURCES = ['curl'];
+const DEFAULT_BROWSER_ROUTING_SUBRESOURCES = ['curl', 'telemetry'];
 const BROWSER_ROUTE_CACHEABLE_PATH = /^\/(?:v\d+\/)?browsers(?:\/[^/]+)?\/?$/;
 const BROWSER_POOL_ACQUIRE_PATH = /^\/(?:v\d+\/)?browser_pools\/[^/]+\/acquire\/?$/;
 const BROWSER_DELETE_BY_ID_PATH = /^\/(?:v\d+\/)?browsers\/([^/]+)\/?$/;

tests/lib/browser-routing.test.ts

@@ -381,9 +381,41 @@ describe('browser routing', () => {
     ).rejects.toThrow(/unsupported HTTP method/i);
   });
 
-  test('defaults browser routing subresources to curl when env is unset', async () => {
+  test('defaults browser routing subresources to curl and telemetry when env is unset', async () => {
     await withBrowserRoutingEnv(undefined, async () => {
-      expect(browserRoutingSubresourcesFromEnv()).toEqual(['curl']);
+      expect(browserRoutingSubresourcesFromEnv()).toEqual(['curl', 'telemetry']);
+    });
+  });
+
+  test('routes telemetry stream calls to the VM /telemetry/stream path by default', async () => {
+    await withBrowserRoutingEnv(undefined, async () => {
+      const calls: Array<{ url: string; headers: Headers }> = [];
+      const kernel = new Kernel({
+        apiKey: 'k',
+        baseURL: 'https://api.example/',
+        fetch: async (input, init?: RequestInit) => {
+          const url = normalizeURL(input);
+          const headers = input instanceof Request ? new Headers(input.headers) : new Headers(init?.headers);
+          calls.push({ url, headers });
+          if (url === 'https://api.example/browsers') {
+            return Response.json({
+              session_id: 'sess-1',
+              base_url: 'http://browser-session.test/browser/kernel',
+              cdp_ws_url: 'wss://browser-session.test/browser/cdp?jwt=token-abc',
+            });
+          }
+          return new Response('id: 1\ndata: {"seq":1}\n\n', {
+            status: 200,
+            headers: { 'content-type': 'text/event-stream' },
+          });
+        },
+      });
+
+      await kernel.browsers.create();
+      await kernel.browsers.telemetry.stream('sess-1');
+
+      expect(calls[1]?.url).toBe('http://browser-session.test/browser/kernel/telemetry/stream?jwt=token-abc');
+      expect(calls[1]?.headers.get('authorization')).toBeNull();
     });
   });