AI agents decide and act on their own. When one goes wrong in production, logs won't tell you what it was thinking. Runback replays the agent step by step — so you see the moment it broke, and fix it in minutes instead of days.
An agent chains together dozens of decisions and tool calls. When the result is wrong, the trail is a wall of logs — and nobody can say which step caused it, or why.
Runback turns a run into something you can walk through — and act on.
Every step shows the exact instructions, conversation, and tools the model received — the context that drove its decision.
Re-run a single decision against the original prompt, or change the prompt and a model and compare the outcome side by side.
A failed run opens focused on the step that broke, with the error and the bad input already in view. No scrolling required.
Wrap your agent with withDebugger() — about three lines. Works with the Vercel AI SDK and any model.
As the agent works, Runback captures every reasoning step and tool call — and the full context behind each one.
Open the run, walk the timeline, inspect any step, and replay it. The whole story, end to end.
Open one to walk through it yourself.
Open a real failing run and see the moment it broke for yourself.
Open a failing run →