🌮 MadTaco — MCP Server

npm: @madtaco/mcp

Verification and utility API for AI agents. Validate tax IDs, screen sanctions, verify companies, inspect domains — prepaid USD credits. Failed checks are never charged.

This package is a stdio MCP server that wraps the public MadTaco API at https://api.madtaco.dev/v1. Every response includes credits_charged (0 for free operations). Prefer remote HTTP instead? See HTTP MCP below.

Docs

madtaco.dev — product site
Setup guide — Cursor, Claude, Smithery
API docs — OpenAPI reference
Agent skill — integration guide (MCP + REST)
llms.txt — full endpoint catalog
pricing.json — per-operation prices
Health — API status
Server card — tool metadata

Quick start (stdio)

Terminal

npx @madtaco/mcp

Claude Desktop / Cursor

Claude Desktop config: ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows).
Cursor: .cursor/mcp.json in your project or global MCP settings.

config.json

{
  "mcpServers": {
    "madtaco": {
      "command": "npx",
      "args": ["-y", "@madtaco/mcp"],
      "env": {
        "MADTACO_API_KEY": "your_api_key_here"
      }
    }
  }
}

Without an API key: validate_tax_id, validate_iban, lookup_instrument, validate_email (syntax), validate_phone (format), create_account, verify_account.

With an API key (tier registered): get_usage, propose_check.

Funded account required (tier 2): paid screening/verification tools and validate_email/validate_phone full modes. Top up via POST /v1/billing/checkout or madtaco.dev billing.

Rate limits: 50 req/day anonymous (per IP), 100 req/day registered (per API key), 500/day included once funded — see llms.txt.

Try it

Validate the Chilean RUT 11.111.111-1 using MadTaco.

Check whether IBAN DE89370400440532013000 is valid.

Look up ticker CMG on exchange US.

Remote HTTP

Streamable HTTP MCP on the API subdomain — no npm install required:

config.json

{
  "mcpServers": {
    "madtaco": {
      "url": "https://api.madtaco.dev/mcp",
      "headers": { "X-Api-Key": "your_api_key_here" }
    }
  }
}

Authenticate with X-Api-Key or Authorization: Bearer. Same 13 tools as this stdio package.

Environment

Variable	Required	Default
`MADTACO_API_KEY`	For authenticated and paid tools	—
`MADTACO_API_BASE`	No	`https://api.madtaco.dev/v1`

Override for staging or local dev:

json

"env": { "MADTACO_API_BASE": "https://api.madtaco.dev/v1" }

Tools

All paths are relative to MADTACO_API_BASE (default https://api.madtaco.dev/v1).

Tool	API endpoint	Credits
`validate_tax_id`	`POST /validate/tax-id`	0
`validate_iban`	`POST /validate/iban`	0
`lookup_instrument`	`POST /lookup/instrument`	0
`validate_email`	`POST /validate/email`	0 (syntax) / 0.005 (full, tier 2)
`validate_phone`	`POST /validate/phone`	0 (format) / 0.005 (full, tier 2)
`screen_sanctions`	`POST /screen/sanctions`	0.10
`verify_company`	`POST /verify/company`	0.15
`inspect_domain`	`POST /inspect/domain`	0.05
`screen`	`POST /screen` + optional `GET /screens/{id}?wait=60`	sum of completed checks
`propose_check`	`POST /propose`	pledge hold only
`create_account`	`POST /accounts`	0
`verify_account`	`POST /accounts/verify`	0
`get_usage`	`GET /usage`	0

Not in MCP (REST only)

Call these directly against the API — see llms.txt:

GET /data/cl/{indicator} — Chilean indicators (UF, UTM, USD, EUR, IPC)
GET /balance — credit balance (get_usage includes balance)
GET /evidence/{id} — signed evidence URLs
GET /health — uptime check

Agent onboarding flow

create_account with an email → account_id + pending_verification
Human or agent reads the 6-digit code from email
verify_account → api_key (tier registered)
Fund the account via madtaco.dev billing or POST /v1/billing/checkout
Set MADTACO_API_KEY and run paid checks

Credentials never transit through MCP responses for human dashboard access — use POST /v1/accounts/invite-human when needed.

Development

Stdio transport only — this server calls the public HTTP API; no database or secrets beyond an optional API key.

bash

git clone https://github.com/madtaco-dev/mcp.git
cd mcp
npm install
npm test
npm run build
MADTACO_API_KEY=... npm run dev

New tools ship as minor npm releases as the API grows. See llms.txt for the current tool list.

MadTaco README