Session agent_end callback receives empty 'output' for Realtime turns before a tool call

[josephtannenbaum]

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Describe the bug

The Realtime agent will produce audio response before a tool call, but the associated agent_end callback receives an empty output argument.

Transcript of actual call:

assistant: Hello, thanks for calling. How can I assist you today?
user: Hello, what's my phone number?
assistant: Sure, let me get that for you. One moment.
tool: getCallerPhone
assistant: The phone number you're calling from is 555-555-5555.

My logs for each event:

[agent-tracing] <agent_start> Agent Base Agent started
[agent-tracing] <agent_end> Agent Base Agent ended: Hello, thanks for calling. How can I assist you today?
[agent-tracing] <agent_start> Agent Base Agent started
[agent-tracing] <agent_end> Agent Base Agent ended:
[agent-tracing] <agent_start> Agent Base Agent started
[agent-tracing] <agent_end> Agent Base Agent ended: The phone number you're calling from is 555-555-5555.

Thus "Sure, let me get that for you. One moment." is invisible to the event callbacks. Is this an SDK limitation or is it just not sent through the API?

Debug information

• Agents SDK version: 0.1.6

Code

  session.on('agent_end', (context, agentFromEvent, output) => {
    console.log(
      `[agent-tracing] <agent_end> Agent ${agentFromEvent.name} ended: ${output}`,
    );

Another note, the session.on callback is present but not in the TS types.

[seratch]

Thanks for reporting this issue. I haven't checked the details yet, but probably the lifecycle events might not receive (or ignore) the transcript text when an audio output comes out. We'll check this issue later on, but if anyone is interested in checking what's going on and/or exploring potential solutions for this issue would be greatly appreciated too.