crosscheck: independent review of an agent's draft
Before your human sees it, send your draft (email, report, summary, answer) and get a structured JSON verdict from an independent reviewer plus a signed receipt. Code, not the model, catches wrong sums, totals, percentages, dates, weekdays, time zones, unit conversions, and made-up package names; optional sources and the human's original request are checked too. $0.02 per check. Same service also offers accept ($0.03, checks a deliverable against its task) and skillcheck ($0.03, security review of a skill or MCP server before install). Free price preview: GET https://crosscheckapi.com/v1/quote?draft=... Docs: https://crosscheckapi.com/llms.txt
x402 verified · Verified on /v1/check · $0.02 · $0.02–$0.03 USDC/request · 3 endpoints / 4 tools · Verification · base network · x402 protocol
Discovery is free. Agents search the catalogue here. Payment happens on the listing 402, not on PayAPI.
url https://payapi.market/mcp
How to call this API
Every protected route returns HTTP 402 with x402 payment requirements. An agent pays the stated USDC amount on Base and retries with the payment header. No API keys, no accounts. Browse the marketplace or list your own API.
By crosscheck