Verify World ID API — Pay Per Call with USDC on Base

verify_worldid API

Verify a World ID 4.0 proof via the Worldcoin Developer Portal API. Generates an RP signature server-side using your signing key, proxies the proof to the Part of the x402 Gateway — $0.005 per call, settled in USDC on Base. No accounts, no API keys: agents pay per request via the x402 protocol.

How payment works

Send a POST to https://x402.freeq.one/tools/verify_worldid without a payment header and the API replies 402 Payment Required with an x402 challenge (payTo address, USDC amount, Base network). A paying agent signs the USDC payment and retries with the X-PAYMENT header — settlement is verified on-chain in seconds and the API response returns with an X-PAYMENT-RESPONSE receipt.

Example call

curl -X POST https://x402.freeq.one/tools/verify_worldid \
  -H "Content-Type: application/json" \
  -d '{"proof":{"protocol_version":"4.0","responses":[{"identifier":"proof_of_human","issuer_schema_id":1,"nullifier":"0x...","expires_at_min":49012345,"proof":["0x...","0x...","0x...","0x...","0x..."],"signal_hash":"0x..."}]},"action":"test_action"}'

Browse every pay-per-call API on the all APIs page, or inspect the machine-readable service card and OpenAPI spec.