Capturing Traces

NVIDIA OO Agents traces every agent method call, LLM call, code execution, and tool invocation as OpenTelemetry spans using OpenInference semantic conventions. Traces are grouped by session.id and nested by call hierarchy.

Automatic tracing (zero config)

Every Agent.__init__() auto-attempts tracing once per process: it probes the trace viewer at http://localhost:5001 (or $OTLP_ENDPOINT) and, if reachable, streams spans to it. Nothing to import, nothing to call:

nooa start-dev            # terminal 1: viewer + OTLP receiver on :5001
uv run python my_agent.py    # terminal 2: traces appear automatically

If the viewer is not reachable, tracing is silently disabled. There is NO automatic fallback to files. The only exception: if you explicitly set OTLP_ENDPOINT and it's unreachable, a warning is printed to stderr. If you need traces without a viewer, use explicit file export (below).

Explicit tracing

from nooa.tracing import enable_tracing, exporters, flush_traces