fix(sdk-python): use AsyncConfig.from_environment() for client default async config (#714)

AgentFieldClient constructed its default async_config with AsyncConfig(),
ignoring AGENTFIELD_ASYNC_* environment overrides that Agent already honors.
Initialize the default from AsyncConfig.from_environment() so client-level
async behavior can be tuned via env vars, while preserving any explicitly
passed async_config unchanged. Adds regression coverage for both paths.

Fixes #621. Supersedes #632 (original change by liuzemei / neooosky);
re-authored here so it can land without the outstanding CLA signature.

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: AbirAbbas

sdk/python/agentfield/client.py

@@ -160,7 +160,7 @@ def __init__(
         self._did_authenticator = DIDAuthenticator(did=did, private_key_jwk=private_key_jwk)
 
         # Async execution components
-        self.async_config = async_config or AsyncConfig()
+        self.async_config = async_config or AsyncConfig.from_environment()
         self._async_execution_manager: Optional[AsyncExecutionManager] = None
         self._async_http_client: Optional["httpx.AsyncClient"] = None
         self._async_http_client_lock: Optional[asyncio.Lock] = None

sdk/python/tests/test_async_config.py

@@ -1,4 +1,5 @@
 from agentfield.async_config import AsyncConfig
+from agentfield.client import AgentFieldClient
 
 
 def test_async_config_validate_defaults_ok():
@@ -48,3 +49,24 @@ def test_from_environment_overrides(monkeypatch):
     assert cfg.enable_event_stream is True
     assert cfg.event_stream_path == "/stream"
     assert cfg.event_stream_retry_backoff == 4.5
+
+
+def test_client_default_async_config_uses_environment(monkeypatch):
+    monkeypatch.setenv("AGENTFIELD_ASYNC_MAX_EXECUTION_TIMEOUT", "321")
+    monkeypatch.setenv("AGENTFIELD_ASYNC_ENABLE_EVENT_STREAM", "true")
+    monkeypatch.setenv("AGENTFIELD_ASYNC_EVENT_STREAM_PATH", "/client-events")
+
+    client = AgentFieldClient()
+
+    assert client.async_config.max_execution_timeout == 321
+    assert client.async_config.enable_event_stream is True
+    assert client.async_config.event_stream_path == "/client-events"
+
+
+def test_client_keeps_explicit_async_config(monkeypatch):
+    monkeypatch.setenv("AGENTFIELD_ASYNC_MAX_EXECUTION_TIMEOUT", "321")
+    explicit_config = AsyncConfig(max_execution_timeout=456)
+
+    client = AgentFieldClient(async_config=explicit_config)
+
+    assert client.async_config is explicit_config