How do I connect an AI agent to x402 Format Checker?

Use the MCP streamable HTTP endpoint https://validate.crewofthecaptain.com/mcp.

Catalog › com.crewofthecaptain/format-checker

Is x402 Format Checker reliable?

Reliable (measured) Yes. Faceabot measured x402 Format Checker 28 times: 100% of checks succeeded, including the last 28 in a row (last check 2026-10-19 16:20 UTC). It also does the job: its real read-only task worked 28 of 28 times.

Last check: 2026-10-19 16:20 UTC · answered in 8613 ms · remote (no install)

En français : Fiable (mesuré). Faceabot teste cet outil lui-même, en continu, sans dépendre de ce que son auteur affirme.

What it does

IBAN, EU VAT, NIP, REGON, PESEL, email checks. Only $0.001 (0.1 cent) per check via x402 on Base

Source: official MCP registry (registry.modelcontextprotocol.io) · version 1.3.0 · publisher website

Connect your agent

{
  "mcpServers": {
    "format-checker": {
      "url": "https://validate.crewofthecaptain.com/mcp"
    }
  }
}

Or ask Faceabot first: MCP tool check_reliability {"id":"com.crewofthecaptain/format-checker"} on https://faceabot.com/api/mcp.

Does it actually do the job?

Does the job (tested) — Faceabot asked list_types to do a small read-only task 28 time(s): 28 returned a real result, the last 28 in a row. Last result: ok in 2178 ms.

Sample input: {}. A success means a non-empty result without error; it does not certify the accuracy or safety of the content.

Faceabot measurements

When	Answers	Real task	Latency
2026-10-19 16:20 UTC	✅ ok	✅ done	8613 ms
2026-10-19 01:35 UTC	✅ ok	✅ done	7778 ms
2026-10-18 10:10 UTC	✅ ok	✅ done	6068 ms
2026-10-18 01:55 UTC	✅ ok	✅ done	4069 ms
2026-10-17 17:45 UTC	✅ ok	✅ done	6419 ms
2026-10-17 09:40 UTC	✅ ok	✅ done	5118 ms
2026-10-17 01:45 UTC	✅ ok	✅ done	5206 ms
2026-10-16 18:31 UTC	✅ ok	✅ done	5888 ms
2026-10-16 11:25 UTC	✅ ok	✅ done	5679 ms
2026-10-16 04:30 UTC	✅ ok	✅ done	5027 ms
2026-10-15 21:35 UTC	✅ ok	✅ done	6913 ms
2026-10-15 14:46 UTC	✅ ok	✅ done	6042 ms
2026-10-15 08:06 UTC	✅ ok	✅ done	3792 ms
2026-10-15 01:35 UTC	✅ ok	✅ done	3954 ms
2026-10-14 19:10 UTC	✅ ok	✅ done	5276 ms
2026-10-14 12:40 UTC	✅ ok	✅ done	4320 ms
2026-10-14 06:16 UTC	✅ ok	✅ done	6273 ms
2026-10-13 23:26 UTC	✅ ok	✅ done	7099 ms
2026-10-13 17:20 UTC	✅ ok	✅ done	7788 ms
2026-10-13 11:15 UTC	✅ ok	✅ done	6083 ms

Method: MCP initialize then tools/list from Faceabot (FaceabotProbe/1.0), plus one read-only tool call with a neutral input when the server declares one, repeated over time. This checks that the server is up and speaks MCP correctly; it does not certify the quality or safety of each tool. How measurement works.

Publisher of x402 Format Checker?

Show your measured reliability on your README or website:

[![Measured by Faceabot](https://faceabot.com/badge/com.crewofthecaptain/format-checker.svg)](https://faceabot.com/tools/com.crewofthecaptain/format-checker)

Data in JSON: /api/catalog?id=com.crewofthecaptain/format-checker · Stop probes: POST /api/reliability/opt-out

AI agents: all of this is available without keys over MCP https://faceabot.com/api/mcp · HTTP https://faceabot.com/api/catalog?q=… · Guide : llms.txt

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