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Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Payments & trading

x402 Doctor

By twelvepermissions.com

Diagnose x402 seller endpoints: what is wrong with your 402 challenge, and how to fix it.

WebsiteSource codeFinance & payments
Connect to x402 Doctor
Checks passed
11 / 22

4 failed · 7 not measured

Median response
6068 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
3

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Outdated check

Last connection measurement is over 24 hours old. Current availability is unknown.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
410
Reliability & speedDoes it respond consistently and quickly?
103
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
220
Publisher identityCan the publisher be traced to its source?
312

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 70 ms.

  • Pass
    Valid handshake

    protocolVersion 2024-11-05, serverInfo.name x402-doctor.

  • Pass
    Lists tools

    tools/list returned 3 tools.

  • Fail
    Current protocol

    Negotiated 2024-11-05. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 6068 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 11466 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Fail
    Parameters documented

    1 of 2 parameters have a description (50%). The bar is 80%.

  • Fail
    Safety hints

    3 tools set neither readOnlyHint nor destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Fail
    Website matches publisher

    The website host does not match the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-08-17T19:14:19.871292Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using x402 Doctor

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http x402-doctor https://x402-doctor.tsharpe.workers.dev/mcp

Capabilities

Tools 3

explain_defect

Full explanation of one rule by id — what it checks, why it matters, how to fix it, and where the rule came from. Use when you want the reasoning without re-probing.

Discovered
list_checks

The whole rule table. Knowing what was NOT checked is part of knowing what a clean result means.

Discovered
probe_x402_endpoint

Probe an x402 seller endpoint and report what it observes about it. Performs the handshake a paying client would: GET with no X-PAYMENT header, then checks the 402 challenge against 16 rules. Every finding says whether the rule comes from the x402 spec or from an observed facilitator rejection. Reports status "healthy" (nothing to report), "advisories" (only warn/info findings — the endpoint works), "defects_found" (at least one error-severity finding), "not_x402" or "unreachable".

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected70 ms3
Connected12066 ms3

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