Maintain legacy resource/operation names for backwards compatibility

Author: jboolean

ddtrace/contrib/internal/mcp/patch.py

@@ -17,8 +17,8 @@
 from ddtrace.internal.logger import get_logger
 from ddtrace.internal.utils.formats import asbool
 from ddtrace.llmobs._integrations.mcp import CLIENT_TOOL_CALL_OPERATION_NAME
-from ddtrace.llmobs._integrations.mcp import REQUEST_RESPONDER_ENTER_OPERATION_NAME
-from ddtrace.llmobs._integrations.mcp import REQUEST_RESPONDER_RESPOND_OPERATION_NAME
+from ddtrace.llmobs._integrations.mcp import SERVER_REQUEST_OPERATION_NAME
+from ddtrace.llmobs._integrations.mcp import SERVER_TOOL_CALL_OPERATION_NAME
 from ddtrace.llmobs._integrations.mcp import MCPIntegration
 from ddtrace.llmobs._utils import _get_attr
 from ddtrace.propagation.http import HTTPPropagator
@@ -231,9 +231,13 @@ def traced_request_responder_enter(mcp, pin: Pin, func, instance, args: tuple, k
         if headers:
             activate_distributed_headers(pin.tracer, config.mcp, headers)
 
+    operation_name = (
+        SERVER_TOOL_CALL_OPERATION_NAME if isinstance(request_root, CallToolRequest) else SERVER_REQUEST_OPERATION_NAME
+    )
+
     span = integration.trace(
         pin,
-        REQUEST_RESPONDER_ENTER_OPERATION_NAME,
+        operation_name,
         submit_to_llmobs=True,
         span_name="mcp.{}".format(_get_attr(request_root, "method", "unknown")),
     )
@@ -263,18 +267,16 @@ async def traced_request_responder_respond(mcp, pin: Pin, func, instance, args:
     integration: MCPIntegration = mcp._datadog_integration
     span: Optional[Span] = getattr(instance, "_dd_span", None)
 
-    result = await func(*args, **kwargs)
-
     if span:
         integration.llmobs_set_tags(
             span,
             args=args,
             kwargs=dict(**kwargs, request_responder=instance),
             response=None,
-            operation=REQUEST_RESPONDER_RESPOND_OPERATION_NAME,
+            operation=SERVER_REQUEST_OPERATION_NAME,
         )
 
-    return result
+    return await func(*args, **kwargs)
 
 
 def patch():

ddtrace/llmobs/_integrations/mcp.py

@@ -24,8 +24,9 @@
 MCP_SPAN_TYPE = "_ml_obs.mcp_span_type"
 
 CLIENT_TOOL_CALL_OPERATION_NAME = "client_tool_call"
-REQUEST_RESPONDER_ENTER_OPERATION_NAME = "request_responder"
-REQUEST_RESPONDER_RESPOND_OPERATION_NAME = "request_responder_respond"
+SERVER_REQUEST_OPERATION_NAME = "server_request"
+# This operation is handled the same as server_request but has a different name for legacy reasons
+SERVER_TOOL_CALL_OPERATION_NAME = "server_tool_call"
 
 
 def _find_client_session_root(span: Optional[Span]) -> Optional[Span]:
@@ -90,7 +91,7 @@ def _llmobs_set_tags(
             self._llmobs_set_tags_client(span, args, kwargs, response)
         elif operation == "initialize":
             self._llmobs_set_tags_initialize(span, args, kwargs, response)
-        elif operation == REQUEST_RESPONDER_RESPOND_OPERATION_NAME:
+        elif operation == SERVER_REQUEST_OPERATION_NAME or operation == SERVER_TOOL_CALL_OPERATION_NAME:
             self._llmobs_set_tags_request_responder_respond(span, args, kwargs, response)
         elif operation == "list_tools":
             self._llmobs_set_tags_list_tools(span, args, kwargs, response)

tests/contrib/mcp/test_mcp_llmobs.py

@@ -16,9 +16,7 @@ def _assert_distributed_trace(mock_tracer, llmobs_events, expected_tool_name):
 
     all_spans = [span for trace in traces for span in trace]
     client_spans = [span for span in all_spans if span.resource == "client_tool_call"]
-    server_spans = [
-        span for span in all_spans if span.name == "mcp.tools/call" and span.resource == "request_responder"
-    ]
+    server_spans = [span for span in all_spans if span.resource == "server_tool_call"]
     client_events = [event for event in llmobs_events if "MCP Client Tool Call" in event["name"]]
     server_events = [
         event