feat(telemetry): add gen_ai.agent.version metric

Author: Achuth17

src/google/adk/agents/base_agent.py

@@ -115,6 +115,12 @@ class MyAgent(BaseAgent):
   Agent name cannot be "user", since it's reserved for end-user's input.
   """
 
+  version: str = ''
+  """The agent's version.
+
+  Version of the agent being invoked. Used to identify the Agent involved in telemetry.
+  """
+
   description: str = ''
   """Description about the agent's capability.
 
@@ -678,6 +684,7 @@ def __create_kwargs(
 
     kwargs: Dict[str, Any] = {
         'name': config.name,
+        'version': config.version,
         'description': config.description,
     }
     if config.sub_agents:

src/google/adk/agents/base_agent_config.py

@@ -55,6 +55,10 @@ class BaseAgentConfig(BaseModel):
 
   name: str = Field(description='Required. The name of the agent.')
 
+  version: str = Field(
+      default='', description='Optional. The version of the agent.'
+  )
+
   description: str = Field(
       default='', description='Optional. The description of the agent.'
   )

src/google/adk/telemetry/tracing.py

@@ -82,6 +82,9 @@
 
 USER_CONTENT_ELIDED = '<elided>'
 
+# TODO: move to semconv and remove this.
+GEN_AI_AGENT_VERSION = 'gen_ai.agent.version'
+
 # Needed to avoid circular imports
 if TYPE_CHECKING:
   from ..agents.base_agent import BaseAgent
@@ -155,6 +158,7 @@ def trace_agent_invocation(
   span.set_attribute(GEN_AI_AGENT_DESCRIPTION, agent.description)
 
   span.set_attribute(GEN_AI_AGENT_NAME, agent.name)
+  span.set_attribute(GEN_AI_AGENT_VERSION, agent.version)
   span.set_attribute(GEN_AI_CONVERSATION_ID, ctx.session.id)
 
 
@@ -455,6 +459,7 @@ def use_generate_content_span(
       USER_ID: invocation_context.session.user_id,
       'gcp.vertex.agent.event_id': model_response_event.id,
       'gcp.vertex.agent.invocation_id': invocation_context.invocation_id,
+      GEN_AI_AGENT_VERSION: invocation_context.agent.version,
   }
   if (
       _is_gemini_agent(invocation_context.agent)

tests/unittests/telemetry/test_spans.py

@@ -24,6 +24,7 @@
 from google.adk.models.llm_response import LlmResponse
 from google.adk.sessions.in_memory_session_service import InMemorySessionService
 from google.adk.telemetry.tracing import ADK_CAPTURE_MESSAGE_CONTENT_IN_SPANS
+from google.adk.telemetry.tracing import GEN_AI_AGENT_VERSION
 from google.adk.telemetry.tracing import trace_agent_invocation
 from google.adk.telemetry.tracing import trace_call_llm
 from google.adk.telemetry.tracing import trace_inference_result
@@ -119,6 +120,34 @@ async def test_trace_agent_invocation(mock_span_fixture):
       mock.call('gen_ai.operation.name', 'invoke_agent'),
       mock.call('gen_ai.agent.description', agent.description),
       mock.call('gen_ai.agent.name', agent.name),
+      mock.call(GEN_AI_AGENT_VERSION, ''),
+      mock.call(
+          'gen_ai.conversation.id',
+          invocation_context.session.id,
+      ),
+      mock.call(USER_ID, invocation_context.session.user_id),
+  ]
+  ]
+  mock_span_fixture.set_attribute.assert_has_calls(
+      expected_calls, any_order=True
+  )
+  assert mock_span_fixture.set_attribute.call_count == len(expected_calls)
+
+@pytest.mark.asyncio
+async def test_trace_agent_invocation_with_version(mock_span_fixture):
+  """Test trace_agent_invocation sets span attributes correctly when version is provided."""
+  agent = LlmAgent(name='test_llm_agent', model='gemini-pro')
+  agent.description = 'Test agent description'
+  agent.version = '1.0.0'
+  invocation_context = await _create_invocation_context(agent)
+
+  trace_agent_invocation(mock_span_fixture, agent, invocation_context)
+
+  expected_calls = [
+      mock.call('gen_ai.operation.name', 'invoke_agent'),
+      mock.call('gen_ai.agent.description', agent.description),
+      mock.call('gen_ai.agent.name', agent.name),
+      mock.call(GEN_AI_AGENT_VERSION, agent.version),
       mock.call(
           'gen_ai.conversation.id',
           invocation_context.session.id,
@@ -767,6 +796,7 @@ async def test_generate_content_span(
 
   mock_span.set_attributes.assert_called_once_with({
       GEN_AI_AGENT_NAME: invocation_context.agent.name,
+      GEN_AI_AGENT_VERSION: '',
       GEN_AI_CONVERSATION_ID: invocation_context.session.id,
       USER_ID: invocation_context.session.user_id,
       'gcp.vertex.agent.event_id': 'event-123',