NumberBroom MCP Server

A remote MCP server that lets AI agents (Claude, ChatGPT, and other MCP-compatible clients) verify US phone numbers through the NumberBroom API: carrier-level line type, carrier name, an activity score, and TCPA litigator status.

This server is a thin, stateless proxy. It has no database and runs no OAuth flow — it forwards your NumberBroom API key straight through to https://numberbroom.com/api/v1, which already owns authentication, rate limiting, billing, and abuse protection. See numberbroom.com/developers for the underlying REST API this wraps.

Tools

Get an API key

1. Sign up at numberbroom.com and add credit to your account.

2. Generate an API key at numberbroom.com/settings.

Connect a client

Add this server as a remote MCP connection using its deployed URL, https://numberbroom.com/mcp, with your NumberBroom API key as a Bearer token in the Authorization header:

Authorization: Bearer nb_live_YOUR_KEY

Exactly how you set that header depends on the client — most MCP-capable apps that support remote servers let you add a custom header per connection.

Local development

npm install
npm run dev

This starts the server at http://localhost:8787/mcp via wrangler dev.

Deploy

npm run deploy

Deploys to Cloudflare Workers as numberbroom-mcp. Requires a Cloudflare account authenticated via wrangler login.

Why a proxy, not a rewrite

Every tool call here is a direct, unmodified pass-through to NumberBroom's own /api/v1 endpoints. That means:

• Auth, rate limiting (5,000 lookups/key/day), the circuit breaker, and billing are all enforced exactly once, by NumberBroom's own API — this server does not duplicate or second-guess any of it.

• A number that fails to parse costs nothing, same as calling the REST API directly.

• This server never sees or stores your API key beyond the lifetime of a single request; each MCP tool call constructs an isolated server instance with no shared state between callers.

License

MIT