Testing

Retrace

Replay and debug AI agent failures by forking the exact step that broke, then prove your fix before shipping

retraceai.tech

Verified API available Free tier

Quick facts
What is it	Replay and debug AI agent failures by forking the exact step that broke, then prove your fix before shipping
Pricing	Freemium — from $29/mo
Free tier	Yes
Platform	Web Application
API	Yes
Best for	Debugging production AI agent failures, Testing prompt or tool changes before deployment
Domain registered	2026

Data updated July 2, 2026

What does Retrace do?

Retrace is a debugging and reliability platform built specifically for AI agents. Think of it as a CI/CD pipeline for agent behavior — it records every LLM call, tool invocation, and error your agent makes, then lets you re-run the whole thing and branch from the exact moment something went wrong. Instead of staring at logs and guessing, you get a full trace you can scrub, fork, and fix.

Getting started is surprisingly simple. You add a single Python decorator (`@retrace.record`) to your agent function, and Retrace automatically captures calls to OpenAI, Anthropic, Gemini, or any other LLM. From there, you can replay a failed run step-by-step, fork a new branch from the broken step, edit the prompt or tool input, and re-run to see if it works. The platform also includes a "prove-the-fix" feature that returns a verdict — pass or fail — so you know your change is solid before you deploy. Beyond replay, Retrace offers detection (groundedness gaps, drift, failure clusters), enforcement (circuit breakers, budget limits, pre-call gateways), and evaluation (CI gates, datasets, eval rules).

This tool is a godsend for any developer building or maintaining AI agents — whether you're using LangChain, CrewAI, LlamaIndex, or rolling your own. Instead of treating agent failures as black-box mysteries, you get reproducible, forkable recordings that turn a production incident into a regression test you can fix and verify. If you've ever spent hours chasing why a multi-step agent went off the rails, Retrace gives you a sanity-saving workflow: record, fork, fix, prove.

Developer Tools Testing

#ai agents#ci-cd#debugging#llm#observability#python sdk#testing#typescript-sdk

Key features

What makes it stand out

One decorator captures every LLM and tool call for automatic trace recording

Replay any recorded run or fork from the exact step that broke

Prove-the-fix verdict: re-run against the failed run and get a pass/fail check before deploying

Built-in detection of groundedness gaps, drift, and failure clusters

Guardrails and circuit breakers that halt runaway loops or budget overruns in real time

Who is Retrace for?

Who benefits most from this tool

Debugging production AI agent failures

Testing prompt or tool changes before deployment

Building regression test suites for agent behavior

Pricing

Free tier available — start without a credit card

Free

1 users
7 retention days
1,000 traces per month
1,000 traces/mo
7-day retention
Fork & replay: $5/mo add-on
1 user

Starter

$29.0/month

1 users
30 retention days
10,000 traces per month
10,000 traces/mo
30-day retention
100 fork replays/mo
Cassette VCR replay
25 prove-the-fix runs/mo
1 user

Pro

$99.0/month

1 users
90 retention days
50,000 traces per month
50,000 traces/mo
90-day retention
Unlimited fork replays
Cassette VCR replay
200 prove-the-fix runs/mo
1 user
CI regression gates
Multi-agent detectors
Sandbox env: 5,000 traces/mo

Teams

$399.0/month

10 users
365 retention days
500,000 traces per month
500,000 traces/mo
365-day retention
Unlimited fork replays
Cassette VCR replay
1,000 prove-the-fix runs/mo
Up to 10 users
Team traces & collaboration
CI regression gates
Multi-agent detectors
Sandbox env: 50,000 traces/mo

Enterprise

Custom

Unlimited users
Custom retention days
Unlimited traces per month
Unlimited traces/mo
Custom retention
Unlimited fork replays
Cassette VCR replay
Unlimited prove-the-fix runs/mo
Unlimited users
Team traces & collaboration
CI regression gates
Multi-agent detectors
Sandbox env: Unlimited traces/mo

Trust & presence

Domain Domain registered 2026

Gallery

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