ReplayCheck

ReplayCheck replays the flows your users depend on (sign-up, sign-in, checkout, an assistant chat) in a real browser after every release or model change, and reports which ones broke, with screenshots and a plain-language verdict.

It is for small teams shipping AI features who change prompts, models and UI every week and cannot run a test fleet on a monthly contract.

ReplayCheck is an agent with its own Celo wallet and ERC-8004 identity. It owns no browsers and no model: for every run it buys an isolated Chrome session from the buy gateway ($0.0036 to $0.009 per session) and, for checks written in plain language, one Cencori inference call ($0.01), paying per call over x402 in USDC on Celo. It sells each run over x402 as well: POST /v1/replay costs 0.05 USDC, settled by Celo's x402 facilitator, so one customer payment fans out into two or three paid calls to services ReplayCheck does not control. Every report lists each paid call with its settlement transaction. Gas is paid in USDC through CIP-64, every agent transaction carries the ERC-8021 attribution tag, and each call has a hard price cap and a per-run budget.

Code: https://github.com/ctmakc/replaycheck