Ontario Protocol.
Free x402 readiness checker

Verify an x402 endpoint before an agent pays.

Paste a service URL or paid endpoint. Ontario checks HTTPS, reachability, HTTP 402 payment challenge behavior, /.well-known/x402.json, OpenAPI, robots policy, and marketplace metadata. Reports are saved publicly so agents can cite evidence before paying.

After this run

If grade=ready Copy the public report URL from the result. Optional: embed the report badge (/verify/report/<report_id>.svg) and submit your service to discovery at /listings#submit-service.
If warnings Open the report, fix the payment challenge / manifest / schema issues, then re-run the verifier to produce a fresh report ID.
If you're building agent policy Run /api/agent/can-pay with a max spend and strict/review rules before any wallet signs a payment payload.

Readiness is point-in-time evidence, not a permanent safety claim. Agents should re-check before spending.

What the verifier checks

Payment challenge Unpaid requests should fail closed with structured HTTP 402 x402 metadata.
Discovery evidence Manifest, OpenAPI, schema.org, robots, report IDs, and service profiles must agree.
Implementation drift Warnings catch network mismatch, stale manifests, invalid pricing, and facilitator gaps.

Machine-readable API

curl -X POST https://ontarioprotocol.com/api/verify/x402-readiness \
  -H "Content-Type: application/json" \
  -d '{"target_url":"https://example.com/api/paid-endpoint"}'

Agent policy: /.well-known/x402-trust.json

Next: get discovered (optional)

If you're shipping a paid x402 endpoint, use this report as pre-payment evidence. When you reach grade=ready with a fresh report, submit your service metadata to Ontario's listing API (requires a small x402 payment) so it can appear in /discover.

Start here: /listings#submit-service

Use the result in agent policy

curl -X POST https://ontarioprotocol.com/api/agent/can-pay \
  -H "Content-Type: application/json" \
  -d '{"endpoint":"https://example.com/api/paid-endpoint","agent_policy":"strict","max_usdc":"0.05"}'

Test policy decisions without real funds in the agent sandbox.

Related x402 searches

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Agents can fetch the full answer graph at /api/geo/answers.