Attest

io.github.attestagentsPublished by GitHub account attestagentsv1.0.0Updated Oct 24, 2026

Scan agent payment endpoints (x402, AP2, L402, MPP, 402) for a trust grade A-F before paying.

VerifiedStreamable HTTPWeb executableFinanceSecurity & Monitoring

Overview

AI-generated overview

Attest lets an AI agent scan x402, AP2, L402, MPP and HTTP 402 payment endpoints for an A–F trust grade and safety verdict before it pays.

What you can do
  • Scan a payment endpoint URL for a letter grade, composite score, verdict, danger flags, price and report link
  • Look up the most recent grade already recorded for a host as a quick pre-check
  • Verify a live 402 payment offer at the moment of spend, returning allow, warn or block with machine-readable reasons such as wallet mismatch or price swaps
When to use it
Use it when an agent pays autonomously over x402-style protocols and you want a deterministic safety check in the payment loop before authorizing a payment to an unfamiliar or untrusted endpoint.
Requirements
Either the hosted remote endpoint over Streamable HTTP, or the npm package attest-mcp run locally with Node.js 18 or newer over stdio (for example via npx). No API key or account is required. The optional ATTEST_BASE_URL variable overrides the API base URL for self-hosting or testing.
Before you install
Scanned URLs and results are logged to Attest's public directory, so do not scan endpoints whose URL or response contains private or sensitive information. Grading runs on Attest's servers and requests go out to that third party. The verdict is advisory: it does not itself execute or block payments, so the agent's own payment logic must honor it.

Installation

In SourceWeft

  1. Open Attest in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.

Use with an agent

Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.

Read https://sourceweft.com/mcp/io.github.attestagents%2Fattest-mcp/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.

Read the install guide the agent follows

Other MCP clients

Add this to your client's mcpServers config.

{
  "mcpServers": {
    "attest": {
      "type": "http",
      "url": "https://attestagent.org/api/mcp"
    }
  }
}

README

Attest MCP Server

[npm version] [npm downloads] [License: MIT] [Node.js]

Trust scanning for agent payments — right inside your AI agent.

attest-mcp is a Model Context Protocol server that lets any MCP-compatible agent (Claude, Cursor, Windsurf, VS Code, and more) scan an agent payment endpoint and get back a letter grade A–F with a clear safety verdict before authorizing a single cent.

It covers the agentic payment protocols in use today: x402, MPP, AP2, L402, and HTTP 402.

Powered by Attest. The scoring engine runs entirely on Attest's servers — this package is a thin client that relays requests, so installing it never exposes any proprietary grading logic.

Why

Autonomous agents are starting to pay for things on their own. A single malicious or misconfigured endpoint can drain funds through impersonation, a blocklisted payout wallet, bait-and-switch pricing, or a broken payment handshake. attest-mcp gives your agent a fast, deterministic safety check it can run as a step in its payment loop.

Tools

ToolWhat it does
attest_scanRuns a full scan on a payment endpoint URL and returns a grade (A–F), a composite score (0–100), a verdict, danger flags, price, and a link to the full report. Call this before paying an unfamiliar endpoint.
attest_gradeFast lookup of the most recent grade for a host that has already been scanned. Good for a quick pre-check.

Requirements

  • Node.js 18 or newer
  • Any MCP-compatible client

No API key required.

Quick start

Run it directly with npx (no install needed):

bash
npx attest-mcp

The server speaks MCP over stdio, so you normally don't run it by hand — you point your MCP client at it using one of the configs below.

Client setup

Claude Desktop

Edit claude_desktop_config.json (Settings → Developer → Edit Config):

json
{  "mcpServers": {    "attest": {      "command": "npx",      "args": ["-y", "attest-mcp"]    }  }}

Cursor

Add to ~/.cursor/mcp.json (or Settings → MCP → Add new server):

json
{  "mcpServers": {    "attest": {      "command": "npx",      "args": ["-y", "attest-mcp"]    }  }}

Windsurf

Add to ~/.codeium/windsurf/mcp_config.json:

json
{  "mcpServers": {    "attest": {      "command": "npx",      "args": ["-y", "attest-mcp"]    }  }}

VS Code

Add to .vscode/mcp.json in your workspace:

json
{  "servers": {    "attest": {      "command": "npx",      "args": ["-y", "attest-mcp"]    }  }}

Any other MCP client

Use the command npx -y attest-mcp with the stdio transport.

Remote server (no install)

Prefer not to install anything? Attest also runs a hosted MCP server you can connect to over Streamable HTTP:

https://attestagent.org/api/mcp

Point any remote-MCP-capable client at that URL.

Usage example

Once connected, just ask your agent in natural language:

"Before you pay, scan https://api.example.com/paid-resource with Attest."

The agent calls attest_scan and gets back something like:

json
{  "host": "api.example.com",  "grade": "A",  "composite": 95,  "danger": false,  "verdict": "Valid endpoint, established host.",  "priceHuman": "0.01 USDC",  "reportUrl": "https://attestagent.org/r/abc-123"}

Configuration

Environment variableDefaultDescription
ATTEST_BASE_URLhttps://attestagent.orgOverride the Attest API base URL. Only needed for self-hosting or testing.

Security & privacy

  • No secrets, no accounts, no API keys. The server holds no credentials.
  • No proprietary logic ships here. Grading happens server-side; this package only relays requests and formats responses.
  • Inputs are validated before any request is made.
  • Outbound only. The server makes HTTPS requests to the Attest API and speaks MCP over stdio — it opens no inbound ports.
  • Scanned URLs and results are logged to Attest's public directory. Do not scan endpoints whose URL or response contains private or sensitive information. See attestagent.org/legal.

Links

Contributing

Issues and pull requests are welcome — see CONTRIBUTING.md.

License

MIT © Attest

Source: README.md at commit ac54bb5

Tools

2

attest_scan

Scan an agent payment endpoint (x402 / HTTP 402) and return a letter grade A to F with a safety verdict before paying.

Parametersurlrequired

attest_guard

Verify a live 402 payment offer at the moment of spend. Pass the EXACT offer you just received (url, payTo, amount, asset, network) and get an allow / warn / block verdict with machine-readable reasons: wallet mismatch vs the verified payout wallet, price swaps vs the last verified quote, danger flags, blocklisted wallets, and typosquats. Call this AFTER receiving a 402 offer and BEFORE authorizing the payment.

ParametersurlrequiredassetrequiredpayTorequiredamountrequiredschemenetworkrequired

Version history

1
  1. v1.0.0LatestSep 16, 2026

Score

100% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 daysRequired25 pts
  • Auth declaredRequired10 pts
  • Tools listedRequired15 pts
  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts