fix: Demote diagnostic logs to debug and exclude handoff tools from tracking

Chat input and graph structure logs were at INFO level from debugging.
Demote both to DEBUG so they don't surface in production log output.

Handoff tools (transfer_to_*) are a routing workaround, not real tool
calls, so exclude them from LD tool call tracking. on_tool_end now skips
any tool not present in fn_name_to_config_key rather than falling back
to the raw function name.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: jsonbailey

packages/ai-providers/server-ai-langchain/src/ldai_langchain/langgraph_agent_graph_runner.py

@@ -136,7 +136,7 @@ def _message_content_len(msg: Any) -> int:
 def _format_chat_messages_for_log(msgs: List[Any]) -> str:
     """
     One line per message index — matches OpenAI error indices (e.g. messages.[5]).
-    Logged at INFO before each model ainvoke.
+    Logged at DEBUG before each model ainvoke.
     """
     from langchain_core.messages import AIMessage, HumanMessage, SystemMessage, ToolMessage
 
@@ -271,7 +271,7 @@ async def invoke(state: WorkflowState) -> dict:
                     msgs = _coalesce_tool_messages_for_openai(list(state['messages']))
                     if node_instructions:
                         msgs = [SystemMessage(content=node_instructions)] + msgs
-                    log.info(
+                    log.debug(
                         'LangGraphAgentGraphRunner node=%s: CHAT_INPUT (%s messages)\n%s',
                         nk,
                         len(msgs),
@@ -340,7 +340,7 @@ async def invoke(state: WorkflowState) -> dict:
 
         tracker = self._graph.get_tracker()
         graph_key_str = tracker.graph_key if tracker else 'unknown'
-        log.info(
+        log.debug(
             f"LangGraphAgentGraphRunner: graph='{graph_key_str}', root='{root_key}', "
             f"structure: {' | '.join(graph_structure)}"
         )

packages/ai-providers/server-ai-langchain/src/ldai_langchain/langgraph_callback_handler.py

@@ -167,7 +167,10 @@ def on_tool_end(
         if node_key is None:
             return
 
-        config_key = self._fn_name_to_config_key.get(name, name)
+        config_key = self._fn_name_to_config_key.get(name)
+        if config_key is None:
+            # Tool is not a registered functional tool (e.g. a handoff tool) — skip tracking.
+            return
         if node_key not in self._node_tool_calls:
             self._node_tool_calls[node_key] = []
         self._node_tool_calls[node_key].append(config_key)

packages/ai-providers/server-ai-langchain/tests/test_langgraph_callback_handler.py

@@ -289,13 +289,13 @@ def test_on_tool_end_records_tool_call():
     assert handler.node_tool_calls.get('root-agent') == ['get_weather_open_meteo']
 
 
-def test_on_tool_end_falls_back_to_fn_name_when_no_mapping():
-    """Tool end uses the raw function name when no config key mapping exists."""
+def test_on_tool_end_skips_unregistered_tools():
+    """Tool end is ignored for tools not in the fn_name_to_config_key map (e.g. handoff tools)."""
     handler = LDMetricsCallbackHandler({'root-agent'}, {})
     tools_run_id = uuid4()
     handler.on_chain_start({}, {}, run_id=tools_run_id, name='root-agent__tools')
-    handler.on_tool_end('result', run_id=uuid4(), parent_run_id=tools_run_id, name='my_tool')
-    assert handler.node_tool_calls.get('root-agent') == ['my_tool']
+    handler.on_tool_end('result', run_id=uuid4(), parent_run_id=tools_run_id, name='transfer_to_child')
+    assert handler.node_tool_calls.get('root-agent') is None
 
 
 def test_on_tool_end_multiple_tools_accumulated():