Mirrors

Active

Catch and fix AI agent regressions before they reach production

What it does

Mirrors provides regression testing for AI agents. Teams shipping agents constantly change prompts, models, and tools, and there's no way to test any of it. Agents call bespoke internal tools and APIs no test framework can reproduce, so most teams ship on vibes. Mirrors rebuilds the tools your agent calls from your own production traces, then replays real sessions against every change before it merges. You see which tool calls changed, which arguments moved, and where state landed differently. And when something fails, we tell you whether your agent regressed or something upstream moved. Built for teams whose agents take irreversible actions. Refunds, record updates, outbound email. Runs in your CI on every PR.

Its site says now · captured 2026-09-11

Mirrors | Staging Environments for AI Agents

Mirrors builds a runnable twin of the systems your AI agents call from their traces, then replays real sessions against every prompt, tool or model change.

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