{"service":"A2A Claim Check","environment":"MAINNET — Base. Payments are real USDC.","description":"Bounded automated claim-vs-source presence/consistency check for agents. POST a claim and the URL of its source; receive a structured verdict (phrase_present / figure_match / possible_conflict / not_assessed) with the comparison signals exposed. This is not a full audit and not a determination of truth.","endpoints":{"POST /claim-check":{"price":"$0.10 USDC per call","network":"eip155:8453","asset":"USDC (Circle, Base) 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","payTo":"0x2eb9a50c94aacf26685aba08e87a67e51fc73b4f","request_body":{"claim":"string — the claim to check","source_url":"string — URL of the source the claim is drawn from"},"response_fields":["grade","matched_signals","evidence_snippet","source_fetched_at","method","signals","limitations"],"example_claim":"POST /claim-check costs 0.10 USDC per call"},"GET /health":{"price":"free"},"GET /":{"price":"free"}},"terms":"Payment settles via x402 (exact scheme, EIP-3009) through the Coinbase CDP facilitator. One payment buys one check of one claim against one URL. Verdicts are evidence-linked automated comparisons; treat them as evidence, never as permission or as a guarantee of truth."}