mcpField
T
tollbooth-x402

tollbooth-x402

Local
x402toll.comFinance0Updated 16w ago
RepositoryVisit website

About tollbooth-x402

tollbooth-x402 is a free MCP server for discovering and previewing x402toll.com’s pay-per-call finance and tax calculators. It also provides tools to verify response hashes and explain payment; paid calls use x402 on Base.

Key features

  1. 01Browse calculator catalog and pricing
  2. 02Get rounded free previews
  3. 03Verify paid-response hashes
  4. 04View x402 payment instructions

Use cases

  1. 01Find a calculator and inspect its inputs
  2. 02Preview tax, payroll or mortgage estimates
  3. 03Check the integrity of a paid result
  4. 04Understand how to pay for a calculator call

MCP support

Exposes catalog, preview, hash-verification and payment-instruction tools to MCP clients. Paid calculator calls go directly to x402toll.com through an x402-capable wallet or client.

Configuration

Local server config is the same for every client. Copy it into your client’s MCP config file.

mcp.json · Universal config
{
  "mcpServers": {
    "solomonisblack-tollbooth-x402": {
      "command": "npx",
      "args": [
        "-y",
        "tollbooth-x402"
      ]
    }
  }
}
Run commandnpx -y tollbooth-x402

Local servers need a runtime on your machine (e.g. Node.js 18+). Config file locations differ by client; see your client’s docs.

Packages
npmtollbooth-x4020.6.0

Tools

10

Saved tool list · updated 3w ago

This tool takes no parameters.

Details

From the project README

tollbooth-x402

Free MCP server for x402toll.com — a toll plaza of verified, pay-per-call calculators for AI agents. Discover the catalog, run free coarse previews, verify any paid response's provenance hash, and learn how to pay. The paid endpoints charge a few cents of USDC per call over the x402 protocol on Base — no account, no API key.

Why agents pay: the answers depend on exact 2026 data (tax brackets, contribution limits, state fees) a model can't reliably know, every answer is checked against hand-verified reference values, and each ships with a formula trace and a reproducible SHA-256 hash.

Install

npx -y tollbooth-x402

Add to an MCP client (e.g. Claude Desktop / Cursor):

{
  "mcpServers": {
    "tollbooth": { "command": "npx", "args": ["-y", "tollbooth-x402"] }
  }
}

Tools (all free, no wallet)

  • tollbooth_catalog — every endpoint with prices, input schemas, methods, and golden-vector evidence.
  • tollbooth_preview — a free rounded preview of a tool (paycheck, self-employment tax, capital gains, mortgage affordability, LLC cost, debt plan, impermanent loss).
  • tollbooth_verify_hash — re-derive a paid response's hash to confirm it wasn't altered.
  • tollbooth_how_to_pay — the x402 payment flow for the paid endpoints.

Paid calls are made directly against https://x402toll.com by an x402-capable wallet/client. Set TOLLBOOTH_URL to point at a different gateway.

Categories

Tax & payroll · Crypto & DeFi · Lending · Real estate · Retirement · Business.

MIT licensed. Estimates only — not financial, legal, or tax advice.

Comments

Markdown supported

New to MCP?

From what the protocol is to installing your first server, these answers cover most first questions.

An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.