`invoke_agent_span` with `propagate=True` does not propagate `agent_name` and `agent_id` to children spans

[benedict-khoo-sap]

Describe the Bug

I tried instrumenting a langgraph agent with invoke_agent_span and propagate=True and I see a span appearing in CLS with the agent ID and name I provided. However, that same agent (in a single invocation) also produced a span with an agent name of LangGraph and a different agent ID. I expected all the children spans of my invoke_agent_span to inherit the same agent ID and name (because propagate=True).

Steps to Reproduce

1. Clone https://github.tools.sap/Montana-AI-Singapore/a2a-server-samples
2. Check out branch instrumentation-agent-id
3. cd appfnd-langgraph-basic
4. Copy .env.example and fill up the credentials with a valid AI Core and CLS instance
5. uv run app to start the server
6. Invoke the agent. Example curl request

curl --request POST \
  --url http://localhost:10000/v1/message:stream \
  --header 'content-type: application/json' \
  --data '{
  "message": {
    "messageId": "a52d542b-06cb-4e9a-b36e-15ee6cb7eee4",
    "role": "ROLE_USER",
    "content": [
      {
        "text": "5 USD to SGD"
      }
    ]
  }
}'

7. Go to your CLS dashboard -> Dev Tools and use the OpenSearch query (fill up the service name)

GET otel-v1-apm-span-*/_search
{
  "size": 1000,
  "query": {
    "bool": {
      "must": [
        {
          "term": {
             "serviceName": "<WHATEVER_YOU_FILLED_APPFND_CONHOS_APP_NAME_WITH>"
          }
        }
     ]
    }}
    ,
    "sort": [
      { "startTime": { "order": "desc" } }
    ]
}

8. See Expected Behavior

Expected Behavior

In the search result from the repro steps,

• Look for "span.attributes.gen_ai@operation@name": "invoke_agent". There should be 3 spans.
• I expect to see all invoke_agent spans have span.attributes.gen_ai@agent@id with the agent_id value I provided (f268d3fd-096f-4ebc-b7ed-6fc03dfb3dde if you used the value in .env.example). Instead, I see only 2 instances: one with the value I set and another with a different ID. 1 of the invoke_agent spans is missing its span.attributes.gen_ai@agent@id field.
• I expect to see all invoke_agent spans have "span.attributes.gen_ai@agent@name" with the agent_name value I provided (currency-agent-local if you used the value in .env.example). Instead, I see 1 instance of currency-agent-local (as expected) and 2 instances of Langgraph.

Screenshots

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Used Versions

• Python version via python --version: 3.12
• SAP Cloud SDK for Python version: sap-cloud-sdk~=0.6.1

See pyproject.toml in the example for version details

Code Examples

# Your code here

Stack Trace

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Log File

Log file

...

Affected Development Phase

Development

Impact

Impaired

Timeline

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