The time-travel debugger
for AI agents
Other tools show what happened. Rewind lets you fix it — without re-running.
Then run rewind demo && rewind inspect latest — no API keys needed.
The differenceEvery observability tool — Langfuse, LangSmith, Helicone — shows you what happened.
None of them let you change the past and observe a different future.Rewind does.
Chrome DevTools for AI agents
Record, inspect, fork, replay, diff, evaluate — all on the same timeline. The only tool where debugging, tracing, and evals share the same data model.
Fork & Replay
Branch at any step. Fix your code, replay from failure. Steps before the fork are cached — 0 tokens, 0ms. No other tool does this.
Prove the Fix
Score original vs. forked timelines with LLM-as-judge. Correctness, coherence, safety — scored automatically. Ship with evidence, not hope.
Import & Debug
Import production traces from Langfuse, Datadog, or any OTel backend. Fork at the failure, replay locally, export the fix back.
Instant Replay
Identical requests are served from cache at 0 tokens, 0ms latency. Run the same agent 10 times — only the first run hits the LLM.
Evaluation
Datasets, 7 evaluator types, LLM-as-judge, side-by-side experiment comparison. CI-ready with --fail-below thresholds.
Session Sharing
Generate a self-contained HTML file. Open in any browser, share via Slack or email. No install, no login, works offline.
See it in action
Agent fails at step 30? Fix step 30 — not steps 1 through 29 again.
Try it yourself — no API keys needed:
rewind demo && rewind inspect latest
Works with your stack
Already using Langfuse, LangSmith, or Datadog? You don't have to choose. Rewind works alongside them.
LLM Providers
Agent Frameworks
Observability stack
Import traces in, export sessions out, or dual-ship to both.
Start debugging in 30 seconds
One install. One line of code. Zero config.