Payment is a step.
Delivery is the test.
Check payment terms before a call. Check the response against your rules after it. Keep a report you can run again.
Open the workbenchRuns in your browser. No wallet connection.
Bring a response. Leave with evidence.
Build acceptance rules without writing JSON
Add one rule at a time. Rules are visible and editable in the contract above. An exact string needs quotes, such as "USD".
New to batch inputs? Read the example and cost method · Example attempts ↓ · Example contract ↓
128 KiB decoded JSON limit. Inputs stay in this tab, survive tool switches, and are cleared when you reload. Local imports are not uploaded.
Your report will appear here.
Start with the fictional example or paste your own input.
Make the acceptance rule
part of the request.
Useful for invoice extraction, structured research and other agent tasks with a defined JSON output. Decide what “usable” means before paying for another call.
Read the rules & supported profile →- 01
Inspect the offer
Check required fields in an x402 v2 exact EVM challenge. Atomic amounts stay exact; token decimals are never guessed.
- 02
Check the delivered output
Use JSON Pointer paths to require types, exact values and numeric bounds. A rule match is evidence of fit, not proof of truth.
- 03
Repeat after a change
Export your report. Save sanitized fixtures and run the same checks in your own CI with the local runner. Batch checks include entered failure and retry costs in each accepted-output calculation.
Download local runner ↓ · engine.mjs ↓
Would repeated checks solve a real task?
The browser tool is free. Saved history and scheduled checks are a proposal, not available today. €29/month is a price hypothesis, not an offer.
Built on a public specification.
Profile reviewed 19 September 2026. Independent tool; not affiliated with Coinbase or x402.
x402 v2 specification ↗HTTP transport ↗