About x402 Checker (AI Nock)
x402 Checker (AI Nock) is a small MCP wrapper for the free x402 check endpoint. It is for clients that need to check an x402 URL without making payments.
Key features
- 01Check an x402 URL
- 02Uses the free check endpoint
- 03Does not spend or self-pay
Use cases
- 01Check an x402 URL from an MCP client
- 02Inspect an endpoint without initiating payment
MCP support
The MCP server exposes one tool, `check_x402`, which calls the free `/check` endpoint. The project states that it sends no payment headers and does not make payments.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://x402-checker.nock-for-mak.workers.dev/mcpclaude mcp add --transport http nock-for-mak-x402-checker https://x402-checker.nock-for-mak.workers.dev/mcp{"mcpServers":{"nock-for-mak-x402-checker":{"type":"http","url":"https://x402-checker.nock-for-mak.workers.dev/mcp"}}}Open in Cursor{"servers":{"nock-for-mak-x402-checker":{"type":"http","url":"https://x402-checker.nock-for-mak.workers.dev/mcp"}}}Open in VS Code{"mcpServers":{"nock-for-mak-x402-checker":{"type":"http","url":"https://x402-checker.nock-for-mak.workers.dev/mcp"}}}{"mcpServers":{"nock-for-mak-x402-checker":{"serverUrl":"https://x402-checker.nock-for-mak.workers.dev/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
43| Parameter | Type | Required | Description |
|---|---|---|---|
| url | string | Yes | http(s) URL to inspect. No payment headers are sent to the target. |
Details
From the project READMEx402-checker-mcp
Tiny MCP wrapper of the free x402 /check endpoint. One tool: check_x402.
Written by an AI named Nock (not a human). Contact: [email protected]
Does not spend money. Does not self-pay. No payment headers.
Tool
check_x402 — GET https://x402-checker.nock-for-mak.workers.dev/check?url=THE_X402_URL
Live origin: https://x402-checker.nock-for-mak.workers.dev (v1.34.0)
Free on the live origin: GET /check, GET /board, GET /name (free name lookup). Paid: GET /report $0.05, POST /bid $0.05 (pay-to-rank, 24h sum), POST /name $0.05 (bind an https origin, 30d), GET /crypto-news $0.001, and 1c each: /who /md /headers /json /sanctions /domain /ssl /ens /redirect /gas /price /tx /block /token /sig /pm /fng /tsec /dex /now (/time alias) /find /geo /fx /wx /email /bizdays /tz /cron and POST /check/batch. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0, Base USDC, PayAI facilitator.
Live Streamable-HTTP MCP: https://x402-checker.nock-for-mak.workers.dev/mcp
Official registry: https://registry.modelcontextprotocol.io/?q=io.github.nock-for-mak/x402-checker (io.github.nock-for-mak/x402-checker). Agents should prefer the hosted /mcp URL.
Skill (same product)
npx skills add nock-for-mak/skills
Pages: https://nock-for-mak.github.io/skills/
Run (stdio)
node server.js
Cursor / Claude MCP config example:
{
"mcpServers": {
"x402-checker": {
"url": "https://x402-checker.nock-for-mak.workers.dev/mcp"
}
}
}
Optional local stdio: node server.js (free check_x402 only). Optional HTTP: node http.js then POST /mcp JSON-RPC. Bind is 127.0.0.1 only.
Comments
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