fix: propagate custom metadata from RunConfig to InvocationContext

Ensure custom metadata defined in RunConfig is copied to InvocationContext's private custom metadata attribute during model post-initialization. This enables tools to retrieve context-dependent metadata during execution.

PiperOrigin-RevId: 951981807

Author: google-genai-bot

src/google/adk/agents/invocation_context.py

@@ -24,6 +24,7 @@
 from pydantic import ConfigDict
 from pydantic import Field
 from pydantic import PrivateAttr
+from typing_extensions import override
 
 from ..apps._configs import EventsCompactionConfig
 from ..apps._configs import ResumabilityConfig
@@ -272,6 +273,12 @@ class InvocationContext(BaseModel):
   of this invocation.
   """
 
+  @override
+  def model_post_init(self, __context: Any) -> None:
+    super().model_post_init(__context)
+    if self.run_config and self.run_config.custom_metadata:
+      self._custom_metadata.update(self.run_config.custom_metadata)
+
   @property
   def is_resumable(self) -> bool:
     """Returns whether the current invocation is resumable."""

tests/unittests/agents/test_context.py

@@ -135,6 +135,12 @@ def test_actions_property(self, mock_invocation_context):
 
     assert context.actions is context._event_actions
 
+  def test_custom_metadata_property(self, mock_invocation_context):
+    """Test that custom_metadata property delegates to invocation context."""
+    mock_invocation_context._custom_metadata = {"key": "value"}
+    context = Context(mock_invocation_context)
+    assert context.custom_metadata == {"key": "value"}
+
 
 class TestContextListArtifacts:
   """Test the list_artifacts method in Context."""

tests/unittests/agents/test_invocation_context.py

@@ -17,6 +17,7 @@
 from google.adk.agents.base_agent import BaseAgent
 from google.adk.agents.base_agent import BaseAgentState
 from google.adk.agents.invocation_context import InvocationContext
+from google.adk.agents.run_config import RunConfig
 from google.adk.apps import ResumabilityConfig
 from google.adk.events.event import Event
 from google.adk.events.event_actions import EventActions
@@ -127,6 +128,45 @@ def test_get_events_with_no_matching_events(self, mock_invocation_context):
     assert not events
 
 
+class TestInvocationContextInitialization:
+  """Test suite for InvocationContext initialization."""
+
+  def test_custom_metadata_propagation(self):
+    """Tests that custom_metadata from RunConfig is propagated to InvocationContext."""
+    run_cfg = RunConfig(custom_metadata={'test_key': 'test_value'})
+    inv_ctx = InvocationContext(
+        session_service=Mock(spec=BaseSessionService),
+        agent=Mock(spec=BaseAgent),
+        invocation_id='inv_1',
+        session=Mock(spec=Session, events=[]),
+        run_config=run_cfg,
+    )
+    # Access private attribute to verify
+    assert inv_ctx._custom_metadata == {'test_key': 'test_value'}
+
+  def test_custom_metadata_default_empty(self):
+    """Tests that _custom_metadata is empty by default when no RunConfig is provided."""
+    inv_ctx = InvocationContext(
+        session_service=Mock(spec=BaseSessionService),
+        agent=Mock(spec=BaseAgent),
+        invocation_id='inv_1',
+        session=Mock(spec=Session, events=[]),
+    )
+    assert inv_ctx._custom_metadata == {}
+
+  def test_custom_metadata_empty_run_config(self):
+    """Tests that _custom_metadata is empty when RunConfig has no custom_metadata."""
+    run_cfg = RunConfig()
+    inv_ctx = InvocationContext(
+        session_service=Mock(spec=BaseSessionService),
+        agent=Mock(spec=BaseAgent),
+        invocation_id='inv_1',
+        session=Mock(spec=Session, events=[]),
+        run_config=run_cfg,
+    )
+    assert inv_ctx._custom_metadata == {}
+
+
 class TestInvocationContextWithAppResumablity:
   """Test suite for InvocationContext regarding app resumability."""