Execution replay for AI agents

You'll never know
what your agent did.
Until it's too late.

Kairos records every decision, tool call, and failure your AI agents make — and lets you replay it. So when something goes wrong, you know exactly why.

See a replay → pip install kairos-trace

agent.contract_review — production — run #4,417

Agent output

UNSAFE

High confidence. Wrong answer.

Execution trace

00:00 agent.started

00:01 tool.called — document.fetch

00:08 tool.timeout

00:09 retry — 1 of 2

00:14 tool.timeout

00:15 retry — 2 of 2

00:21 context.loss — 34% retrieved

00:22 hallucination.risk.detected

00:24 answer.returned — confidence: HIGH

UNSAFE ■ 2 retries ■ 34% context ■ replay ready ■

The tool didn't fail. The agent did.
Kairos shows you the difference.

How it works

Three steps.
Complete visibility.

Instrument your agents once. Kairos handles capture, replay, and compliance.

Instrument

One import. Every tool call, decision, and failure captured automatically. Works with any agent framework.

from kairos_trace import trace with trace("run") as t: result = agent.run(input)

Replay

Scrub through any execution. Every step. Every context window. Every retry. See exactly what your agent saw.

# Navigate any execution kairos replay --run 4417 kairos diff --event context.loss kairos share --link

Prove

Export a complete audit trail. EU AI Act Article 12. Built in. Regulator-ready, always.

# Export audit trail kairos export --run 4417 \ --format pdf \ --standard eu-ai-act

The failures that logs can't find

Traditional logs tell you
a request happened.

They don't tell you why the agent returned that answer.

A contract review agent read 34% of the document due to a tool timeout. It returned "no issues found" with 94% confidence. The client called three days later.

A customer service agent told a user their refund had been processed. It hadn't. The logs showed a 200 OK. They showed nothing useful.

A financial advice agent made a recommendation after losing its system prompt halfway through a long conversation. Nobody noticed for six weeks.

Kairos replays all of it.

Pricing

Free

£0/mo

For developers evaluating.

500 events
7-day replay
SDK

Get started

You'll never know what your agent did. Until it's too late.

Three steps.Complete visibility.