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name: debug-agent description: >- Root-causes AI agent failures from MLflow traces without requiring a code change, regression suite, scorer, or evaluation run. Use when the user asks to debug, investigate, explain, or determine why an agent produced an output. Prefer an existing matching trace; reproduce only when no usable trace exists.

Debug Agent

Diagnose the failure and report evidence. Do not edit the agent unless the user also asks for a fix; for behavior changes, hand off to fix-agent-issue after the diagnosis.

Workflow

1. Find existing tracing configuration, tracking URI, and experiment. Do not recommend reinstalling or reinstrumenting MLflow when tracing already works.
2. Find a trace matching the reported input, time, session, user, or trace ID. If one exists, use it directly. Do not reproduce a production-only or externally dependent failure merely to satisfy a workflow.
3. Only when no usable trace exists, reproduce the issue once through the normal instrumented entry point and retrieve the resulting trace. If reproduction is unsafe or impossible, state what evidence is missing and stop.
4. Inspect the matching trace span by span. Read assessments first, then inputs, outputs, errors, LLM calls, retrieval results, and tool calls. Use analyze-mlflow-trace for detailed trace anatomy.
5. Correlate trace evidence with source code as needed. Reading source is fine; do not settle on a diagnosis without confirming it against the trace.
6. Report: observed behavior, expected behavior, trace evidence, root cause, confidence, and the smallest likely fix. Do not create tests or scorers for a diagnosis-only request.

Boundaries

• If no trace can be produced because the app is uninstrumented, load instrumenting-with-mlflow-tracing and explain the limitation.
• Log the user's complaint as HUMAN feedback only when a concrete trace is identified and doing so is authorized.
• If the user asks to implement the fix, invoke fix-agent-issue with the trace ID and diagnosis so it can write regression coverage before editing.