feat: add agent span support in langchain instrumentation #3788
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| elif "id" in serialized: | ||
| chain_name = serialized["id"][-1] | ||
|
|
||
| span = self.span_manager.create_chain_span( |
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let's make sure it creates internal span
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Sound good - confirmed chain spans use SpanKind.INTERNAL here:
def create_chain_span(
self,
run_id: UUID,
parent_run_id: Optional[UUID],
chain_name: str,
) -> Span:
"""Create a span for chain execution."""
span = self._create_span(
run_id=run_id,
parent_run_id=parent_run_id,
span_name=f"chain {chain_name}",
kind=SpanKind.INTERNAL,
)
| ) | ||
| span.set_attribute( | ||
| GenAI.GEN_AI_OPERATION_NAME, | ||
| "invoke_agent", |
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Is it possible that the operation name might be changed in the future, if so, declaring it a constant for it might be better.
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Good point - I'm not sure if this semantic convention will change but agree that this should be moved to a constant since it's currently hardcoded in a few places.
| GenAI.GEN_AI_OPERATION_NAME, | ||
| "invoke_agent", | ||
| ) | ||
| if agent_name: |
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If agent_name is None, in that case, should a default value be passed?
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Yeah makes sense, i'll default it to "unknown" for now. Open to suggestions on the naming though.
| span = spans[0] | ||
| assert span.name == "chain TestAgent" | ||
| assert span.kind == SpanKind.INTERNAL | ||
| assert span.attributes.get(GenAI.GEN_AI_AGENT_NAME) == "TestAgent" |
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In the above comment you mentioned that chain spans are internal operations and will not have an operation name but there you are adding assert statements for it, did I miss something?
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Thanks for your review! Let me try to clarify.
Regular chains don't have gen_ai.operation.name since they're just internal operations. However, Agent chains are different. In LangChain's architecture, agents are implemented as chains so we:
- create them using
create_agent_span()(which creates an internal span) - detect if it's actually an agent by checking for
agent_namein metadata - if it is an agent, we add the agent-specific attributes:
gen_ai.agent.namegen_ai.operation.name = "invoke_agent"
I'll update the docstrings to make this distinction clearer.
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Awesome. Thanks for the clarification.
Description
This PR adds agent span support to the LangChain instrumentation following the OpenTelemetry Semantic Conventions for GenAI agent spans. It enables tracing of LangChain agent invocations, chain executions, and agent actions/decisions.
invoke_agentoperation for agent invocationsinvoke_agent {agent_name}andchain {chain_name}gen_ai.agent.name,gen_ai.operation.nameA follow-up PR will add tool execution spans (
execute_tooloperation).Sidenote: Previous PR from our team can be closed.
Type of change
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How Has This Been Tested?
Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration
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Does This PR Require a Core Repo Change?
Checklist:
See contributing.md for styleguide, changelog guidelines, and more.