Lesson 1339 of 2116
Replay and Time-Travel Debugging for Agents
Persist agent traces so you can replay any step with a different model or prompt.
Lesson map
What this lesson covers
Learning path
The main moves in order
- 1The premise
- 2trace replay
- 3deterministic replay
- 4time-travel debug
Concept cluster
Terms to connect while reading
Section 1
The premise
Replayable traces turn flaky agent bugs into reproducible test cases.
What AI does well here
- Capture every model input, output, and tool result with timestamps.
- Replay a trace against a new model version and diff.
- Use replays as regression tests for prompt changes.
What AI cannot do
- Replay non-deterministic external systems perfectly.
- Recreate stochastic model outputs exactly.
Key terms in this lesson
End-of-lesson quiz
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Tutor
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