NameGender MCP server

Turns names, email addresses and usernames into a gender — with the evidence next to every answer: the probability, the sample size, the source and the name it matched.

Works in any client that speaks the Model Context Protocol: Claude Desktop, Claude Code, Cursor and others.

Setup

Get an API key from the namegender.com dashboard. Sign-up needs no card and comes with free credits every day.

Claude Desktop / Claude Code configuration:

config.json

{
  "mcpServers": {
    "namegender": {
      "command": "npx",
      "args": ["-y", "namegender-mcp"],
      "env": { "NAMEGENDER_API_KEY": "ng_live_..." }
    }
  }
}

Claude Code from the command line:

Terminal

claude mcp add namegender -e NAMEGENDER_API_KEY=ng_live_... -- npx -y namegender-mcp

Tools

Tool	What it does
`gender_from_name`	Gender from a first or full name
`gender_from_email`	Extracts a name from the local part of an email address
`gender_from_username`	Extracts a name from a username or handle
`gender_bulk`	Up to 100 values in one request, with a match-rate summary
`name_countries`	Countries a name is recorded in — not a claim about origin
`account_status`	Remaining credits, daily free quota, data version

The gender tools take an optional two-letter country code. The same name can have a different gender from one country to the next; with a code, the answer is weighted by that country's data.

What an answer looks like

Code

Ayşe: female · probability 99% · sample 12,345 · source ssa · country TR

An answer from a source without counts says so:

Code

Kamon: male · probability 95% · no sample (unverified) · source wgnd

The distinction is deliberate. A 95% backed by counted people and a 95% backed by nothing are not the same thing and should not look the same.

Countries are not origin

name_countries keeps two lists apart. Counted birth registrations are published for only seven countries (US, UK, France, Canada, Spain, Ireland, Norway), so the ranked shares compare those seven only. Every other country where the name is recorded appears in a separate, unranked list. Reading the ranking as "where the name comes from" is wrong: Mehmet ranks first in France there, and Turkey is not in the ranking at all.

Errors

Errors do not break the session. The tool returns isError and says what to do — where to top up when credits run out, which variable to check when the key is invalid — and includes the request ID so support can trace it.

Environment variables

Variable	Default
`NAMEGENDER_API_KEY`	(required)
`NAMEGENDER_BASE_URL`	`https://namegender.com/api/v1`

Development

Terminal

npm install
npm test

MIT licensed.

Releasing

Terminal

npm version patch   # also updates server.json
git push --follow-tags

The v* tag runs .github/workflows/release.yml: tests, then npm (trusted publishing, no token), then the MCP registry (GitHub OIDC). Re-running the workflow skips whatever is already published.