Quietforge x402 Tools
Free tools: x402 endpoint directory + probe, on-chain x402 demand signal, sudoku, API pricing.
Connect it
Settings → Connectors → Add custom connector
URL: https://qf-api.quietforge-studio.workers.dev/mcpSettings → Apps & Connectors → Advanced → Developer mode
Create connector with URL: https://qf-api.quietforge-studio.workers.dev/mcp{
"mcpServers": {
"x402-tools": {
"url": "https://qf-api.quietforge-studio.workers.dev/mcp"
}
}
}claude mcp add --transport http x402-tools https://qf-api.quietforge-studio.workers.dev/mcp{
"servers": {
"x402-tools": {
"type": "http",
"url": "https://qf-api.quietforge-studio.workers.dev/mcp"
}
}
}7 tools, verified live
x402_searchread-onlyUse this to find a pay-per-call x402 API for a given task, network or price cap before calling it (mostly USDC on Base; check each row's network and asset, some are testnet or other assets). Searches a health-probed directory of live x402 pay-per-call HTTP endpoints on Base, Solana and other networks (x402_index_stats gives the current count). Returns id, resource URL, method, network, USD price,
x402_serviceread-onlyUse this to check whether one endpoint from x402_search is reliable enough to pay: its record plus its last 20 health probes (status code, latency, alive) and uptime across them.
x402_index_statsread-onlyUse this to see how much this index covers (it is a subset of the x402 market, not all of it) and to sanity-check x402_search coverage before relying on it. Summary of the index: totals, how many endpoints answered on the last probe, counts per network and per source, and when the crawl ran.
x402_demandread-onlyUse this to answer "is anyone actually paying for x402 APIs today" with settled on-chain numbers instead of listings. Market-level demand signal for the x402 ecosystem, verified against on-chain USDC settlement on Base rather than self-reported call counts: how many seller addresses were paid in the last 24h, total USD settled, and the distribution of sellers by payment count. Free and aggregate-o
x402_probeUse this to check a URL you are about to pay (or one you operate) for a well-formed x402 challenge before sending funds; a challenge is no guarantee the service delivers. Makes ONE live unpaid request to a public http(s) URL and reports whether it is an x402 endpoint: status code, latency, alive flag, whether a PAYMENT-REQUIRED challenge came back and the parsed USD price. GET only, except that a
sudoku_puzzleread-onlyUse this when a user wants a sudoku to play or print, or an app needs a verified puzzle at a named difficulty. Generates ONE sudoku puzzle with a unique solution, 180-degree symmetry, graded by the solving techniques it needs (easy | medium | hard | expert). Returns 81-char puzzle and solution strings (row by row, 0 = empty), given count and technique list. Deterministic when a seed is supplied. 2
quietforge_pricingread-onlyPrice-check Quietforge's paid x402 HTTP routes before paying (free read-only list, not tools here): convert docx, xlsx, pptx, csv to pdf; PDF text; URL/HTML to PNG; sudoku books; manuscript typesetting; crosswords; family trees from GEDCOM; dataset quality audits; x402 index API. USD prices, pay-to address, how an x402 client pays.
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