docs(sdk): clarify async stream byte limit scope

Author: abhinav-galileo

sdks/python/src/agent_control/control_decorators.py

@@ -1012,6 +1012,8 @@ def control(policy: str | None = None, step_name: str | None = None) -> Callable
           before replay.
         - The post-check runs on the full buffered output.
         - Chunks are yielded to the caller only after the post-check passes.
+        - stream_buffer_max_bytes limits the normalized post-check payload size,
+          not the in-memory size of replayed chunks.
         - Decorated async generators are pull-only and do not preserve
           interactive asend()/athrow() semantics against the source generator.
 

sdks/python/src/agent_control/settings.py

@@ -64,7 +64,10 @@ class SDKSettings(BaseSettings):
     stream_buffer_max_bytes: int = Field(
         default=5_000_000,
         ge=1,
-        description="Maximum normalized bytes buffered by @control() before failing closed",
+        description=(
+            "Maximum normalized post-check payload bytes buffered by @control() "
+            "before failing closed; does not bound replay-memory usage"
+        ),
     )
 
     # Observability (event batching)