[Bug] TLS error message & documentation for API key auth

If you're using Temporal Cloud with API key authentication for a namespace:

$ tcld namespace auth-method get -namespace quickstart-jack.xxxxx
api_key

And connecting with Python:

TASK_QUEUE = os.environ.get("TASK_QUEUE", "tasks")
TEMPORAL_ADDRESS = os.environ.get("TEMPORAL_ADDRESS", "localhost:7233")
TEMPORAL_NAMESPACE = os.environ.get("TEMPORAL_NAMESPACE", "default")
TEMPORAL_API_KEY = os.environ.get("TEMPORAL_API_KEY", "")

async def main() -> None:
    client = await Client.connect(TEMPORAL_ADDRESS, namespace=TEMPORAL_NAMESPACE, api_key=TEMPORAL_API_KEY)
    executor = ThreadPoolExecutor()
    worker = Worker(
        client,
        task_queue=TASK_QUEUE,
        workflows=load_workflows(),
        activities=load_activities(),
        activity_executor=executor,
    )
    await worker.run()

This will raise this error:

$ poetry run python worker.py
Traceback (most recent call last):
  File "/Users/pearkes/code/jack/temporal/worker.py", line 75, in <module>
    asyncio.run(main())
    ~~~~~~~~~~~^^^^^^^^
  File "/Users/pearkes/.local/share/uv/python/cpython-3.13.2-macos-aarch64-none/lib/python3.13/asyncio/runners.py", line 195, in run
    return runner.run(main)
           ~~~~~~~~~~^^^^^^
  File "/Users/pearkes/.local/share/uv/python/cpython-3.13.2-macos-aarch64-none/lib/python3.13/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^
  File "/Users/pearkes/.local/share/uv/python/cpython-3.13.2-macos-aarch64-none/lib/python3.13/asyncio/base_events.py", line 725, in run_until_complete
    return future.result()
           ~~~~~~~~~~~~~^^
  File "/Users/pearkes/code/jack/temporal/worker.py", line 62, in main
    client = await Client.connect(TEMPORAL_ADDRESS, namespace=TEMPORAL_NAMESPACE, api_key=TEMPORAL_API_KEY)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/pearkes/code/jack/temporal/.venv/lib/python3.13/site-packages/temporalio/client.py", line 177, in connect
    await temporalio.service.ServiceClient.connect(connect_config),                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/pearkes/code/jack/temporal/.venv/lib/python3.13/site-packages/temporalio/service.py", line 209, in connect
    return await _BridgeServiceClient.connect(config)                                                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^                                                       File "/Users/pearkes/code/jack/temporal/.venv/lib/python3.13/site-packages/temporalio/service.py", line 1212, in connect                                                                            await client._connected_client()
  File "/Users/pearkes/code/jack/temporal/.venv/lib/python3.13/site-packages/temporalio/service.py", line 1225, in _connected_client                                                                  self._bridge_client = await temporalio.bridge.client.Client.connect(
                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    ...<2 lines>...                                                                                           )                                                                                                         ^
  File "/Users/pearkes/code/jack/temporal/.venv/lib/python3.13/site-packages/temporalio/bridge/client.py", line 97, in connect                                                                        await temporalio.bridge.temporal_sdk_bridge.connect_client(                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        runtime._ref, config                                                                                      ^^^^^^^^^^^^^^^^^^^^
    ),                                                                                                        ^
RuntimeError: Failed client connect: `get_system_info` call error after connection: Status { code: Unknown, message: "transport error", source: Some(tonic::transport::Error(Transport, hyper::Error(Io, Kind(ConnectionReset)))) }

1. Status { code: Unknown, message: "transport error" ... is quite inscrutable and could be considerably improved.
2. You need to set TLS to True – this wasn't clear in the getting started docs, nor were API keys as an auth method mentioned. I found a reference to it in the Python client docs and figured that may be it.

This works:

TASK_QUEUE = os.environ.get("TASK_QUEUE", "tasks")
TEMPORAL_ADDRESS = os.environ.get("TEMPORAL_ADDRESS", "localhost:7233")
TEMPORAL_NAMESPACE = os.environ.get("TEMPORAL_NAMESPACE", "default")
TEMPORAL_API_KEY = os.environ.get("TEMPORAL_API_KEY", "")
TEMPORAL_TLS = bool(os.environ.get("TEMPORAL_TLS", False))

async def main() -> None:
    client = await Client.connect(TEMPORAL_ADDRESS, namespace=TEMPORAL_NAMESPACE, api_key=TEMPORAL_API_KEY, tls=TEMPORAL_TLS)
    # Use a thread pool executor for synchronous activities
    executor = ThreadPoolExecutor()
    worker = Worker(
        client,
        task_queue=TASK_QUEUE,
        workflows=load_workflows(),
        activities=load_activities(),
        activity_executor=executor,
    )
    await worker.run()

Start with the Python Client.connect example and the Temporal Cloud getting-started documentation linked in the report, reproducing the connection with API-key authentication and TLS omitted. Done means the transport error is more understandable and the documentation clearly covers API keys and the required TLS setting.