tool and agent names in span titles

[jcaplan]

Description

i'm using phoenix. it's not ideal to have to click on each agent or tool to find out what it is. "agent run" and "running tools" is a bit too generic.

References

No response

[DouweM]

@alexmojaki What are your thoughts here? I notice that we have a more complete message on the logfire.msg attribute, but the span names themselves are very bare bones

[alexmojaki]

'agent run' is a mistake: it should have the agent name in it (not just in the message) and really it should be invoke_agent {name} based on https://opentelemetry.io/docs/specs/semconv/gen-ai/gen-ai-agent-spans/#invoke-agent-span. But changing this comes with compatibility concerns as it could break existing queries. See internal discussion in https://pydantic.slack.com/archives/C081LUCJ4KX/p1756382574232799

'running tool' should be execute_tool {gen_ai.tool.name} based on https://opentelemetry.io/docs/specs/semconv/gen-ai/gen-ai-spans/#execute-tool-span, similar situation to the above.

'running tools' doesn't have much information in the message either. I personally think the span should just be removed, see #1434 and https://pydantic.slack.com/archives/C081LUCJ4KX/p1743167443990059

[jcaplan]

here's how my trace looks right now after adding an agent and tool wrapper to insert spans with the agent names, and running a subagent as a tool and the subagent itself calls a tool. I don't have access to those conversations about backwards compatibility but this feels very excessive as a new user and something that is a small detail but really affects the ease of debugging large traces. I'm not sure why there is a doubled agent span but this is 4-5 levels of unnecessary depth to be able to see agent and tool name in the trace.

another related issue I noticed playing around with tool retries as suggested in #2586 is that exception messages are also not propagated properly.

when I insert an extra span in my toolsetwrapper I can see the error message:

but the running tool span does not show the error message properly:

It seems like the error message should be attached to the "event":

vs.

[DouweM]

@alexmojaki Are you planning to work on getting the span names in line with the spec? I also wouldn't mind removing the running tools span, at the very least when there is only one tool.

another related issue I noticed playing around with tool retries as suggested in #2586 is that exception messages are also not propagated properly.

@jcaplan Can you file a new issue for this please?

[alexmojaki]

Opened #2964