Fix Client(model_api_key=...) and remove OPENAI_API_KEY/MODEL_API_KEY env var auto loading

examples/local_browser_playwright_example.py

@@ -104,7 +104,6 @@ def main() -> None:
         browserbase_api_key=bb_api_key,
         browserbase_project_id=bb_project_id,
         model_api_key=model_api_key,
-        local_openai_api_key=model_api_key,
         local_ready_timeout_s=30.0,
     ) as client:
         print("⏳ Starting Stagehand session (local server + local browser)...")

examples/local_example.py

@@ -5,7 +5,7 @@
 Required environment variables:
 - BROWSERBASE_API_KEY (can be any value in local mode)
 - BROWSERBASE_PROJECT_ID (can be any value in local mode)
-- MODEL_API_KEY (used for client configuration even in local mode)
+- MODEL_API_KEY (read by this example and passed explicitly to the client)
 
 
 Install the published wheel before running this script:
@@ -45,13 +45,14 @@ def _stream_to_result(stream, label: str) -> object | None:
 
 def main() -> None:
     load_example_env()
+    # The example reads MODEL_API_KEY itself so the SDK configuration stays explicit.
     model_key = os.environ.get("MODEL_API_KEY")
     if not model_key:
         sys.exit("Set MODEL_API_KEY to run the local server.")
 
     client = Stagehand(
         server="local",
-        local_openai_api_key=model_key,
+        model_api_key=model_key,
         local_ready_timeout_s=30.0,
     )
 

examples/local_server_multiregion_browser_example.py

@@ -75,7 +75,6 @@ def main() -> None:
         browserbase_api_key=bb_api_key,
         browserbase_project_id=bb_project_id,
         model_api_key=model_api_key,
-        local_openai_api_key=model_api_key,
         local_ready_timeout_s=30.0,
     ) as client:
         print("⏳ Starting Stagehand session (local server + Browserbase browser)...")

src/stagehand/_client.py

@@ -24,7 +24,7 @@
 from ._models import FinalRequestOptions
 from ._version import __version__
 from ._streaming import Stream as Stream, AsyncStream as AsyncStream
-from ._exceptions import APIStatusError, StagehandError
+from ._exceptions import APIStatusError
 from ._base_client import (
     DEFAULT_MAX_RETRIES,
     SyncAPIClient,
@@ -52,7 +52,7 @@ class Stagehand(SyncAPIClient):
     # client options
     browserbase_api_key: str | None
     browserbase_project_id: str | None
-    model_api_key: str
+    model_api_key: str | None
 
     def __init__(
         self,
@@ -67,7 +67,6 @@ def __init__(
         local_headless: bool = True,
         local_chrome_path: str | None = None,
         local_ready_timeout_s: float = 10.0,
-        local_openai_api_key: str | None = None,
         local_shutdown_on_close: bool = True,
         base_url: str | httpx.URL | None = None,
         timeout: float | Timeout | None | NotGiven = not_given,
@@ -93,7 +92,10 @@ def __init__(
         This automatically infers the following arguments from their corresponding environment variables if they are not provided:
         - `browserbase_api_key` from `BROWSERBASE_API_KEY`
         - `browserbase_project_id` from `BROWSERBASE_PROJECT_ID`
-        - `model_api_key` from `MODEL_API_KEY`
+
+        `model_api_key` is intentionally not inferred from any AI provider environment variable.
+        Pass it explicitly when you want the SDK to send `x-model-api-key` on remote requests or
+        to forward `MODEL_API_KEY` to the local SEA child process.
         """
         self._server_mode: Literal["remote", "local"] = server
         self._local_stagehand_binary_path = _local_stagehand_binary_path
@@ -102,7 +104,6 @@ def __init__(
         self._local_headless = local_headless
         self._local_chrome_path = local_chrome_path
         self._local_ready_timeout_s = local_ready_timeout_s
-        self._local_openai_api_key = local_openai_api_key
         self._local_shutdown_on_close = local_shutdown_on_close
 
         if browserbase_api_key is None:
@@ -113,12 +114,6 @@ def __init__(
         self.browserbase_api_key = browserbase_api_key
         self.browserbase_project_id = browserbase_project_id
 
-        if model_api_key is None:
-            model_api_key = os.environ.get("MODEL_API_KEY")
-        if model_api_key is None:
-            raise StagehandError(
-                "The model_api_key client option must be set either by passing model_api_key to the client or by setting the MODEL_API_KEY environment variable"
-            )
         self.model_api_key = model_api_key
 
         self._sea_server: SeaServerManager | None = None
@@ -127,14 +122,13 @@ def __init__(
             if base_url is None:
                 base_url = "http://127.0.0.1"
 
-            openai_api_key = local_openai_api_key or os.environ.get("OPENAI_API_KEY") or model_api_key
             self._sea_server = SeaServerManager(
                 config=SeaServerConfig(
                     host=local_host,
                     port=local_port,
                     headless=local_headless,
                     ready_timeout_s=local_ready_timeout_s,
-                    openai_api_key=openai_api_key,
+                    model_api_key=model_api_key,
                     chrome_path=local_chrome_path,
                     shutdown_on_close=local_shutdown_on_close,
                 ),
@@ -210,7 +204,7 @@ def _bb_project_id_auth(self) -> dict[str, str]:
     @property
     def _llm_model_api_key_auth(self) -> dict[str, str]:
         model_api_key = self.model_api_key
-        return {"x-model-api-key": model_api_key}
+        return {"x-model-api-key": model_api_key} if model_api_key else {}
 
     @property
     @override
@@ -236,7 +230,6 @@ def copy(
         local_headless: bool | None = None,
         local_chrome_path: str | None = None,
         local_ready_timeout_s: float | None = None,
-        local_openai_api_key: str | None = None,
         local_shutdown_on_close: bool | None = None,
         base_url: str | httpx.URL | None = None,
         timeout: float | Timeout | None | NotGiven = not_given,
@@ -283,9 +276,6 @@ def copy(
             local_ready_timeout_s=local_ready_timeout_s
             if local_ready_timeout_s is not None
             else self._local_ready_timeout_s,
-            local_openai_api_key=local_openai_api_key
-            if local_openai_api_key is not None
-            else self._local_openai_api_key,
             local_shutdown_on_close=local_shutdown_on_close
             if local_shutdown_on_close is not None
             else self._local_shutdown_on_close,
@@ -340,7 +330,7 @@ class AsyncStagehand(AsyncAPIClient):
     # client options
     browserbase_api_key: str | None
     browserbase_project_id: str | None
-    model_api_key: str
+    model_api_key: str | None
 
     def __init__(
         self,
@@ -355,7 +345,6 @@ def __init__(
         local_headless: bool = True,
         local_chrome_path: str | None = None,
         local_ready_timeout_s: float = 10.0,
-        local_openai_api_key: str | None = None,
         local_shutdown_on_close: bool = True,
         base_url: str | httpx.URL | None = None,
         timeout: float | Timeout | None | NotGiven = not_given,
@@ -381,7 +370,10 @@ def __init__(
         This automatically infers the following arguments from their corresponding environment variables if they are not provided:
         - `browserbase_api_key` from `BROWSERBASE_API_KEY`
         - `browserbase_project_id` from `BROWSERBASE_PROJECT_ID`
-        - `model_api_key` from `MODEL_API_KEY`
+
+        `model_api_key` is intentionally not inferred from any AI provider environment variable.
+        Pass it explicitly when you want the SDK to send `x-model-api-key` on remote requests or
+        to forward `MODEL_API_KEY` to the local SEA child process.
         """
         self._server_mode: Literal["remote", "local"] = server
         self._local_stagehand_binary_path = _local_stagehand_binary_path
@@ -390,7 +382,6 @@ def __init__(
         self._local_headless = local_headless
         self._local_chrome_path = local_chrome_path
         self._local_ready_timeout_s = local_ready_timeout_s
-        self._local_openai_api_key = local_openai_api_key
         self._local_shutdown_on_close = local_shutdown_on_close
 
         if browserbase_api_key is None:
@@ -401,27 +392,20 @@ def __init__(
         self.browserbase_api_key = browserbase_api_key
         self.browserbase_project_id = browserbase_project_id
 
-        if model_api_key is None:
-            model_api_key = os.environ.get("MODEL_API_KEY")
-        if model_api_key is None:
-            raise StagehandError(
-                "The model_api_key client option must be set either by passing model_api_key to the client or by setting the MODEL_API_KEY environment variable"
-            )
         self.model_api_key = model_api_key
 
         self._sea_server: SeaServerManager | None = None
         if server == "local":
             if base_url is None:
                 base_url = "http://127.0.0.1"
 
-            openai_api_key = local_openai_api_key or os.environ.get("OPENAI_API_KEY") or model_api_key
             self._sea_server = SeaServerManager(
                 config=SeaServerConfig(
                     host=local_host,
                     port=local_port,
                     headless=local_headless,
                     ready_timeout_s=local_ready_timeout_s,
-                    openai_api_key=openai_api_key,
+                    model_api_key=model_api_key,
                     chrome_path=local_chrome_path,
                     shutdown_on_close=local_shutdown_on_close,
                 ),
@@ -497,7 +481,7 @@ def _bb_project_id_auth(self) -> dict[str, str]:
     @property
     def _llm_model_api_key_auth(self) -> dict[str, str]:
         model_api_key = self.model_api_key
-        return {"x-model-api-key": model_api_key}
+        return {"x-model-api-key": model_api_key} if model_api_key else {}
 
     @property
     @override
@@ -523,7 +507,6 @@ def copy(
         local_headless: bool | None = None,
         local_chrome_path: str | None = None,
         local_ready_timeout_s: float | None = None,
-        local_openai_api_key: str | None = None,
         local_shutdown_on_close: bool | None = None,
         base_url: str | httpx.URL | None = None,
         timeout: float | Timeout | None | NotGiven = not_given,
@@ -570,9 +553,6 @@ def copy(
             local_ready_timeout_s=local_ready_timeout_s
             if local_ready_timeout_s is not None
             else self._local_ready_timeout_s,
-            local_openai_api_key=local_openai_api_key
-            if local_openai_api_key is not None
-            else self._local_openai_api_key,
             local_shutdown_on_close=local_shutdown_on_close
             if local_shutdown_on_close is not None
             else self._local_shutdown_on_close,

src/stagehand/lib/sea_server.py

@@ -24,7 +24,7 @@ class SeaServerConfig:
     port: int
     headless: bool
     ready_timeout_s: float
-    openai_api_key: str | None
+    model_api_key: str | None
     chrome_path: str | None
     shutdown_on_close: bool
 
@@ -118,6 +118,26 @@ def __init__(
     def base_url(self) -> str | None:
         return self._base_url
 
+    def _build_process_env(self, *, port: int) -> dict[str, str]:
+        proc_env = dict(os.environ)
+        # Force production mode so inherited NODE_ENV=development never reaches the
+        # SEA child process. Development mode breaks under SEA because pino-pretty
+        # is an optional dependency that is not present in the packaged binary.
+        proc_env["NODE_ENV"] = "production"
+        # Server package expects BB_ENV to be set (see packages/server/src/lib/env.ts)
+        proc_env.setdefault("BB_ENV", "local")
+        proc_env["HOST"] = self._config.host
+        proc_env["PORT"] = str(port)
+        proc_env["HEADLESS"] = "true" if self._config.headless else "false"
+        # Always set MODEL_API_KEY in the child env so the SDK constructor value wins
+        # over any inherited parent MODEL_API_KEY. An empty string preserves the
+        # "explicitly unset" case instead of silently reusing the parent's value.
+        proc_env["MODEL_API_KEY"] = self._config.model_api_key or ""
+        if self._config.chrome_path:
+            proc_env["CHROME_PATH"] = self._config.chrome_path
+            proc_env["LIGHTHOUSE_CHROMIUM_PATH"] = self._config.chrome_path
+        return proc_env
+
     def ensure_running_sync(self) -> str:
         with self._lock:
             if self._proc is not None and self._proc.poll() is None and self._base_url is not None:
@@ -169,20 +189,7 @@ def _start_sync(self) -> tuple[str, subprocess.Popen[bytes]]:
 
         port = _pick_free_port(self._config.host) if self._config.port == 0 else self._config.port
         base_url = _build_base_url(host=self._config.host, port=port)
-
-        proc_env = dict(os.environ)
-        # Defaults that make the server boot under SEA (avoid pino-pretty transport)
-        proc_env.setdefault("NODE_ENV", "production")
-        # Server package expects BB_ENV to be set (see packages/server/src/lib/env.ts)
-        proc_env.setdefault("BB_ENV", "local")
-        proc_env["HOST"] = self._config.host
-        proc_env["PORT"] = str(port)
-        proc_env["HEADLESS"] = "true" if self._config.headless else "false"
-        if self._config.openai_api_key:
-            proc_env["OPENAI_API_KEY"] = self._config.openai_api_key
-        if self._config.chrome_path:
-            proc_env["CHROME_PATH"] = self._config.chrome_path
-            proc_env["LIGHTHOUSE_CHROMIUM_PATH"] = self._config.chrome_path
+        proc_env = self._build_process_env(port=port)
 
         preexec_fn = None
         creationflags = 0
@@ -221,18 +228,7 @@ async def _start_async(self) -> tuple[str, subprocess.Popen[bytes]]:
 
         port = _pick_free_port(self._config.host) if self._config.port == 0 else self._config.port
         base_url = _build_base_url(host=self._config.host, port=port)
-
-        proc_env = dict(os.environ)
-        proc_env.setdefault("NODE_ENV", "production")
-        proc_env.setdefault("BB_ENV", "local")
-        proc_env["HOST"] = self._config.host
-        proc_env["PORT"] = str(port)
-        proc_env["HEADLESS"] = "true" if self._config.headless else "false"
-        if self._config.openai_api_key:
-            proc_env["OPENAI_API_KEY"] = self._config.openai_api_key
-        if self._config.chrome_path:
-            proc_env["CHROME_PATH"] = self._config.chrome_path
-            proc_env["LIGHTHOUSE_CHROMIUM_PATH"] = self._config.chrome_path
+        proc_env = self._build_process_env(port=port)
 
         preexec_fn = None
         creationflags = 0

tests/test_client.py

@@ -24,7 +24,7 @@
 from stagehand._utils import asyncify
 from stagehand._models import BaseModel, FinalRequestOptions
 from stagehand._streaming import Stream, AsyncStream
-from stagehand._exceptions import APIStatusError, StagehandError, APITimeoutError, APIResponseValidationError
+from stagehand._exceptions import APIStatusError, APITimeoutError, APIResponseValidationError
 from stagehand._base_client import (
     DEFAULT_TIMEOUT,
     HTTPX_DEFAULT_TIMEOUT,
@@ -464,22 +464,21 @@ def test_validate_headers(self) -> None:
         request = client._build_request(FinalRequestOptions(method="get", url="/foo"))
         assert request.headers.get("x-model-api-key") == model_api_key
 
-        with pytest.raises(StagehandError):
-            with update_env(
-                **{
-                    "BROWSERBASE_API_KEY": Omit(),
-                    "BROWSERBASE_PROJECT_ID": Omit(),
-                    "MODEL_API_KEY": Omit(),
-                }
-            ):
-                client2 = Stagehand(
-                    base_url=base_url,
-                    browserbase_api_key=None,
-                    browserbase_project_id=None,
-                    model_api_key=None,
-                    _strict_response_validation=True,
-                )
-                client2.sessions.start(model_name="openai/gpt-5-nano")
+        with update_env(
+            BROWSERBASE_API_KEY=Omit(),
+            BROWSERBASE_PROJECT_ID=Omit(),
+        ):
+            client2 = Stagehand(
+                base_url=base_url,
+                browserbase_api_key=None,
+                browserbase_project_id=None,
+                model_api_key=None,
+                _strict_response_validation=True,
+            )
+            request = client2._build_request(FinalRequestOptions(method="get", url="/foo"))
+            assert request.headers.get("x-bb-api-key") is None
+            assert request.headers.get("x-bb-project-id") is None
+            assert request.headers.get("x-model-api-key") is None
 
     def test_default_query_option(self) -> None:
         client = Stagehand(
@@ -1512,22 +1511,21 @@ def test_validate_headers(self) -> None:
         request = client._build_request(FinalRequestOptions(method="get", url="/foo"))
         assert request.headers.get("x-model-api-key") == model_api_key
 
-        with pytest.raises(StagehandError):
-            with update_env(
-                **{
-                    "BROWSERBASE_API_KEY": Omit(),
-                    "BROWSERBASE_PROJECT_ID": Omit(),
-                    "MODEL_API_KEY": Omit(),
-                }
-            ):
-                client2 = AsyncStagehand(
-                    base_url=base_url,
-                    browserbase_api_key=None,
-                    browserbase_project_id=None,
-                    model_api_key=None,
-                    _strict_response_validation=True,
-                )
-            _ = client2
+        with update_env(
+            BROWSERBASE_API_KEY=Omit(),
+            BROWSERBASE_PROJECT_ID=Omit(),
+        ):
+            client2 = AsyncStagehand(
+                base_url=base_url,
+                browserbase_api_key=None,
+                browserbase_project_id=None,
+                model_api_key=None,
+                _strict_response_validation=True,
+            )
+            request = client2._build_request(FinalRequestOptions(method="get", url="/foo"))
+            assert request.headers.get("x-bb-api-key") is None
+            assert request.headers.get("x-bb-project-id") is None
+            assert request.headers.get("x-model-api-key") is None
 
     async def test_default_query_option(self) -> None:
         client = AsyncStagehand(