fix(agentserver-core): move agent identity attrs to _on_ending in FoundryEnrichmentSpanProcessor

sdk/agentserver/azure-ai-agentserver-core/azure/ai/agentserver/core/_tracing.py

@@ -277,17 +277,31 @@ def __init__(
         self.project_id = project_id
 
     def on_start(self, span: Any, parent_context: Any = None) -> None:  # pylint: disable=unused-argument
-        if self.agent_name:
-            span.set_attribute(_ATTR_GEN_AI_AGENT_NAME, self.agent_name)
-        if self.agent_version:
-            span.set_attribute(_ATTR_GEN_AI_AGENT_VERSION, self.agent_version)
-        if self.agent_id:
-            span.set_attribute(_ATTR_GEN_AI_AGENT_ID, self.agent_id)
         if self.project_id:
             span.set_attribute(_ATTR_FOUNDRY_PROJECT_ID, self.project_id)
 
-    def _on_ending(self, span: Any) -> None:  # pylint: disable=unused-argument
-        pass
+    def _on_ending(self, span: Any) -> None:
+        # Set agent identity attributes at span end so they cannot be
+        # overwritten by underlying frameworks (e.g. LangChain, Semantic Kernel).
+        #
+        # Workaround: opentelemetry-sdk <=1.40.0 sets _end_time before calling
+        # _on_ending, which causes set_attribute() to silently no-op despite the
+        # spec requiring mutability during OnEnding.  We write to _attributes
+        # directly until the SDK is fixed.  The try/except guards against future
+        # SDK changes that may rename or remove the internal field.
+        # TODO: switch to span.set_attribute() once the SDK honours the spec.
+        attrs = getattr(span, "_attributes", None)
+        if attrs is None:
+            return
+        try:
+            if self.agent_name:
+                attrs[_ATTR_GEN_AI_AGENT_NAME] = self.agent_name
+            if self.agent_version:
+                attrs[_ATTR_GEN_AI_AGENT_VERSION] = self.agent_version
+            if self.agent_id:
+                attrs[_ATTR_GEN_AI_AGENT_ID] = self.agent_id
+        except Exception:  # pylint: disable=broad-exception-caught
+            logger.debug("Failed to enrich span attributes in _on_ending", exc_info=True)
 
     def on_end(self, span: Any) -> None:  # pylint: disable=unused-argument
         pass

sdk/agentserver/azure-ai-agentserver-core/tests/test_tracing.py

@@ -5,15 +5,34 @@
 import os
 from unittest import mock
 
+from opentelemetry.sdk.trace import TracerProvider
+from opentelemetry.sdk.trace.export import SimpleSpanProcessor, SpanExporter, SpanExportResult
+from opentelemetry.sdk.resources import Resource
+
 from azure.ai.agentserver.core import AgentServerHost
 from azure.ai.agentserver.core._config import (
     resolve_agent_name,
     resolve_agent_version,
     resolve_appinsights_connection_string,
 )
+from azure.ai.agentserver.core._tracing import _FoundryEnrichmentSpanProcessor
+
+
+class _CollectorExporter(SpanExporter):
+    """In-memory span collector for tests."""
 
+    def __init__(self):
+        self.spans = []
 
+    def export(self, spans):
+        self.spans.extend(spans)
+        return SpanExportResult.SUCCESS
 
+    def shutdown(self):
+        return True
+
+    def force_flush(self, timeout_millis=30000):
+        return True
 # ------------------------------------------------------------------ #
 # Tracing enabled / disabled
 # ------------------------------------------------------------------ #
@@ -137,6 +156,88 @@ def test_constructor_passes_connection_string(self) -> None:
         mock_configure.assert_called_once_with(connection_string="InstrumentationKey=ctor")
 
 
+# ------------------------------------------------------------------ #
+# FoundryEnrichmentSpanProcessor: attribute timing
+# ------------------------------------------------------------------ #
+
+
+class TestFoundryEnrichmentSpanProcessor:
+    """Agent identity attributes are set in _on_ending so that underlying
+    frameworks (LangChain, Semantic Kernel, etc.) cannot overwrite them.
+
+    Tests use real OTel spans with an in-memory exporter to verify the
+    exported attributes end-to-end.
+    """
+
+    @staticmethod
+    def _create_provider(processor):
+        """Return (TracerProvider, _CollectorExporter) wired with *processor*."""
+        collector = _CollectorExporter()
+        provider = TracerProvider(resource=Resource.create({}))
+        provider.add_span_processor(processor)
+        provider.add_span_processor(SimpleSpanProcessor(collector))
+        return provider, collector
+
+    def test_agent_attrs_present_on_exported_span(self) -> None:
+        proc = _FoundryEnrichmentSpanProcessor(
+            agent_name="my-agent", agent_version="1.0",
+            agent_id="my-agent:1.0", project_id="proj-123",
+        )
+        provider, collector = self._create_provider(proc)
+        tracer = provider.get_tracer("test")
+
+        with tracer.start_as_current_span("span"):
+            pass
+
+        attrs = dict(collector.spans[0].attributes)
+        assert attrs["gen_ai.agent.name"] == "my-agent"
+        assert attrs["gen_ai.agent.version"] == "1.0"
+        assert attrs["gen_ai.agent.id"] == "my-agent:1.0"
+        assert attrs["microsoft.foundry.project.id"] == "proj-123"
+
+    def test_agent_attrs_survive_framework_overwrite(self) -> None:
+        """A framework setting agent attrs mid-span must not win."""
+        proc = _FoundryEnrichmentSpanProcessor(
+            agent_name="my-agent", agent_version="1.0",
+            agent_id="my-agent:1.0", project_id="proj-123",
+        )
+        provider, collector = self._create_provider(proc)
+        tracer = provider.get_tracer("test")
+
+        with tracer.start_as_current_span("span") as span:
+            span.set_attribute("gen_ai.agent.name", "framework-agent")
+            span.set_attribute("gen_ai.agent.id", "framework-agent:0.1")
+
+        attrs = dict(collector.spans[0].attributes)
+        assert attrs["gen_ai.agent.name"] == "my-agent"
+        assert attrs["gen_ai.agent.id"] == "my-agent:1.0"
+
+    def test_none_fields_are_skipped(self) -> None:
+        proc = _FoundryEnrichmentSpanProcessor(
+            agent_name=None, agent_version=None,
+            agent_id=None, project_id=None,
+        )
+        provider, collector = self._create_provider(proc)
+        tracer = provider.get_tracer("test")
+
+        with tracer.start_as_current_span("span"):
+            pass
+
+        attrs = dict(collector.spans[0].attributes)
+        assert "gen_ai.agent.name" not in attrs
+        assert "gen_ai.agent.version" not in attrs
+        assert "gen_ai.agent.id" not in attrs
+        assert "microsoft.foundry.project.id" not in attrs
+
+    def test_no_crash_when_span_lacks_attributes(self) -> None:
+        """If the SDK changes internals, _on_ending must not raise."""
+        proc = _FoundryEnrichmentSpanProcessor(
+            agent_name="a", agent_version="1", agent_id="a:1",
+        )
+        fake_span = object()  # no _attributes at all
+        proc._on_ending(fake_span)  # should not raise
+
+
 # ------------------------------------------------------------------ #
 # Agent name / version resolution with new env vars
 # ------------------------------------------------------------------ #