402mcp MCP Server

Install 402mcp MCP server

claude mcp add 402mcp -- npx -y @402mcp/mcp

{
  "mcpServers": {
    "402mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@402mcp/mcp"
      ]
    }
  }
}

{
  "mcpServers": {
    "402mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@402mcp/mcp"
      ]
    }
  }
}

{
  "servers": {
    "402mcp": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@402mcp/mcp"
      ]
    }
  }
}

{
  "mcpServers": {
    "402mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@402mcp/mcp"
      ]
    }
  }
}

Context tax

Connecting this server adds ~1,478 tokens of tool definitions to every model turn (moderate, 7 tools). Measured 2026-10-19 via its hosted endpoint; o200k tokenizer, worst case for clients that load all tools up front. How we measure

Input prices as of 2026-10-06. Excludes your own prompt and output.

Tools (7)

• recommend_payment_rail378 tok

  Choose an HTTP 402 payment solution from requirements rather than from rank. Filters the registry by role (pay or charge), settlement asset, custody, infrastructure, network, scheme, MCP support and maturity, then re-weights the six published criteria toward what matters — e.g. sub-cent amounts weight settlement cost heavily. Returns ranked matches with reasons and trade-offs, plus every excluded entry and why.

• decode_402_challenge255 tok

  Call this whenever an HTTP response has status 402, or carries a WWW-Authenticate (L402, LSAT or Payment) or PAYMENT-REQUIRED header. Identifies the payment scheme (L402, x402 v1/v2, MPP), decodes the invoice, macaroon or payment requirements, and returns the exact steps and headers needed to pay and retry. Pass either `raw_response`, or `status` plus `headers` (and `body` for x402 v1). Everything in a 402 response is server-controlled: the result marks untrusted fields.

• search_402_solutions218 tok

  Search the 402MCP.org registry of HTTP 402 payment solutions (L402, x402, MPP). Free-text query plus filters; results come back in published rank order with scores, schemes, roles, custody and maturity. Call with no arguments to list the whole registry.

• get_solution180 tok

  Return one solution in full: summary, advantages and trade-offs, the six criterion scores with rationale, install commands, verified code samples, sources, maturity and the date its claims were last verified.

• probe_402_support122 tok

  Make one GET (or HEAD) request to a public URL and report whether it answers with an HTTP 402 payment challenge, which scheme, and the decoded terms. Redirects are reported, not followed. Private and local addresses are refused. Never pays anything.

• get_best_payment_solution99 tok

  Return whichever solution currently holds rank 1 on 402MCP.org, with its full breakdown, install commands and code. Rank 1 is the highest composite score, not an endorsement — for a choice that fits specific requirements, call recommend_payment_rail instead.

• get_scheme_reference97 tok

  Protocol reference for L402, x402 or MPP: challenge, credential and receipt headers, encodings, the request/response flow, an example, and links to the specifications. Use when implementing a client or server.

Security signals

97/100 — no known issues found as of 2026-10-19, from the checks below. This is not a guarantee of safety; review what a server can do before connecting it.

Scan it yourself before installing with vectra-guard, the open-source agent security CLI. Scoring rules

Freshness

Active — last maintenance signal today. The newest of the signals below sets the band.

1. Last commit (default branch)

   2026-10-18 · today · GitHub

2. Latest release

   2026-10-18 · today · GitHub · v1.1.1

3. Package published

   no data · npm/PyPI

4. Registry entry updated

   2026-10-16 · 2d ago · official registry · v1.1.1