fix: track SDK language in v4 metadata

.changeset/swift-taxis-listen.md

@@ -0,0 +1,6 @@
+---
+"@browserbasehq/stagehand": patch
+"@browserbasehq/stagehand-python": patch
+---
+
+Track the Stagehand SDK language in Browserbase session and runtime metadata.

packages/sdk-python/src/stagehand/rpc_client.py

@@ -5,6 +5,7 @@
 import json
 from collections.abc import Awaitable, Callable, Coroutine
 from contextlib import suppress
+from importlib.metadata import version
 from typing import Annotated, Literal, Protocol, TypeVar, cast
 
 from pydantic import BaseModel, ConfigDict, Field, JsonValue, TypeAdapter, ValidationError
@@ -13,6 +14,10 @@
 
 _MAX_REQUEST_ID = 9_007_199_254_740_991
 _MAX_PENDING_NOTIFICATIONS = 100
+_STAGEHAND_SDK_CLIENT_INFO = models.ImplementationInfo(
+    name="stagehand-sdk-python",
+    version=version("stagehand"),
+)
 
 ParamsT = TypeVar("ParamsT", bound=BaseModel)
 ResultT = TypeVar("ResultT", bound=BaseModel)
@@ -479,6 +484,7 @@ async def connect_rpc_client(
     )
     client = RPCClient(cdp, request_timeout_ms=command_timeout_ms)
     configure = models.RuntimeConfigureParams(
+        client_info=_STAGEHAND_SDK_CLIENT_INFO,
         cdp_url=cdp.web_socket_debugger_url,
         **({"telemetry": telemetry} if telemetry is not None else {}),
         log_level=models.LogLevel(log_level),

packages/sdk-python/tests/test_rpc_client.py

@@ -1,4 +1,5 @@
 import asyncio
+from importlib.metadata import version
 from typing import ClassVar, cast
 
 import pytest
@@ -487,6 +488,10 @@ async def test_connect_rpc_client_passes_cdp_options_and_configures_the_runtime(
             "id": 1,
             "method": "runtime.configure",
             "params": {
+                "client_info": {
+                    "name": "stagehand-sdk-python",
+                    "version": version("stagehand"),
+                },
                 "cdp_url": "ws://resolved.example/devtools/browser/1",
                 "log_level": "info",
                 "telemetry": {

packages/sdk-ts/src/browserbaseSession.ts

@@ -7,6 +7,7 @@ import {
   type BrowserbaseExtensionSdk,
   type ProvisionedBrowserbaseExtension,
 } from "./browserbaseExtension.js";
+import { STAGEHAND_SESSION_METADATA } from "./sdkIdentity.js";
 
 export type BrowserbaseSessionClient = {
   createSession(
@@ -55,6 +56,10 @@ export function createBrowserbaseSessionClient(
         session = await browserbase.createSession({
           ...params,
           extensionId: extension.extensionId,
+          userMetadata: {
+            ...params.userMetadata,
+            ...STAGEHAND_SESSION_METADATA,
+          },
         });
       } catch (error) {
         await extension.cleanup().catch(() => undefined);

packages/sdk-ts/src/rpcClient.ts

@@ -42,7 +42,7 @@ import {
 import type { StagehandRpcNotification } from "../../protocol/types.js";
 import { z } from "zod/v4";
 import { CDPClient, type ServiceWorkerInfo } from "./cdpClient.js";
-import { STAGEHAND_SDK_VERSION } from "./version.js";
+import { STAGEHAND_SDK_CLIENT_INFO } from "./sdkIdentity.js";
 
 type PendingRequest = {
   method: RPCMethod;
@@ -59,10 +59,6 @@ type RegisteredRequestHandler = {
 const TRACER = trace.getTracer("@browserbasehq/stagehand");
 const W3C_TRACE_CONTEXT_PROPAGATOR = new W3CTraceContextPropagator();
 const MAX_PENDING_NOTIFICATIONS = 100;
-const STAGEHAND_SDK_CLIENT_INFO = {
-  name: "stagehand-sdk-ts",
-  version: STAGEHAND_SDK_VERSION,
-} as const;
 
 const RPCClientOptionsBaseSchema = z
   .object({

packages/sdk-ts/src/sdkIdentity.ts

@@ -0,0 +1,17 @@
+import { STAGEHAND_SDK_VERSION } from "./version.js";
+
+const STAGEHAND_SDK_IDENTITY = {
+  name: "stagehand-sdk-ts",
+  language: "typescript",
+  version: STAGEHAND_SDK_VERSION,
+} as const;
+
+export const STAGEHAND_SDK_CLIENT_INFO = {
+  name: STAGEHAND_SDK_IDENTITY.name,
+  version: STAGEHAND_SDK_IDENTITY.version,
+} as const;
+
+export const STAGEHAND_SESSION_METADATA = {
+  stagehand: "true",
+  stagehand_sdk_language: STAGEHAND_SDK_IDENTITY.language,
+} as const;

packages/sdk-ts/tests/browserbaseSession.test.ts

@@ -52,15 +52,23 @@ describe("Browserbase session creation", () => {
     const session = await client.createSession({
       keepAlive: false,
       region: "eu-central-1",
-      userMetadata: { suite: "unit" },
+      userMetadata: {
+        stagehand: "false",
+        stagehand_sdk_language: "python",
+        suite: "unit",
+      },
     });
 
     expect(provisionExtension).toHaveBeenCalledWith(browserbase);
     expect(createSession).toHaveBeenCalledWith({
       extensionId: "ext_stagehand",
       keepAlive: false,
       region: "eu-central-1",
-      userMetadata: { suite: "unit" },
+      userMetadata: {
+        stagehand: "true",
+        stagehand_sdk_language: "typescript",
+        suite: "unit",
+      },
     });
     expect(session.cdpUrl).toBe("wss://connect.browserbase.com/devtools/browser/session_123");
     expect(session.sessionId).toBe("session_123");