WillItPlug API and MCP server

MCP server

Add it to ChatGPT, Claude or any MCP client as a remote server. Streamable HTTP, no authentication.

https://www.willitplug.com/mcp/

Published in the official MCP Registryunder com.willitplug/willitplug, verified against this domain. In MCP Apps-compatible assistants, check_trip opens a trip checker with the verdict, voltage guidance and a packing checklist.

• check_trip(from, to) - do my plugs fit, do I need an adapter or converter, and what to pack.
• country_plugs(country) - outlet and plug types, voltage and frequency for one country.
• find_countries_by_outlet(type) - every country with outlets of one plug type.
• plug_type(type) - what a plug type is: its standard, whether it is earthed, and which plugs its socket takes.

Countries are English names ("Japan") or ISO codes ("jp"). Plug types are IEC letters from A to O. Every tool is read-only and returns structured content with a declared output schema, plus the same answer as text.

WillItPlug SDK and CLI

The official JavaScript client and command-line tool. Node.js 22 or later, no API key. Install from npm:

npx willitplug-sdk trip us jp
npx willitplug-sdk country it
npm install willitplug-sdk

import { WillItPlug } from "willitplug-sdk";
const trip = await new WillItPlug().trip("us", "jp");
console.log(trip.adapterNeeded, trip.checklist, trip.url);

willitplug-sdk on npm, ordownload version 1.0.0 directly. The CLI accepts ISO country codes and prints JSON. Commands: trip,country, countries and plugs. The SDK includes TypeScript declarations and supports request cancellation with an AbortSignal. MIT-licensed code; please credit WillItPlug when using its data.

JSON API

Static JSON on a CDN, CORS enabled. Countries use lowercase ISO 3166-1 alpha-2 codes.

• /api/v1/countries.json

  Every country: plugs, outlets, voltage, frequency and page URL.

• /api/v1/countries/jp.json

  One country by ISO code, with notes, sources and when it was last checked.

• /api/v1/trips/us/jp.json

  A trip: which plugs fit, whether you need an adapter or converter, and a packing checklist.

• /api/v1/plugs.json

  The plug and socket standards and which plugs each socket takes.

• /api/v1/openapi.json

  OpenAPI 3.1 description of all of the above.

curl https://www.willitplug.com/api/v1/trips/us/jp.json

Every response includes a credit object and the URL of the matching page. Also see llms.txt and the API catalog.

Errors

Errors are JSON too, as RFC 9457 problems with the content type application/problem+json. Branch on code: not_found for a path that doesn't exist, unknown_trip for a trip between unknown or identical countries. detail says how to fix the request.

{
  "type": "https://www.willitplug.com/developers/#errors",
  "title": "No such API resource",
  "status": 404,
  "code": "not_found",
  "detail": "Check the path against /api/v1/openapi.json."
}

Versioning and deprecation

The version is in the path. Within /api/v1/ fields are only added, never renamed or removed, so ignore fields you don't know. A breaking change gets a new path, and the old one keeps working for at least six months, answering with Deprecation and Sunset headers from the day its end date is set. No version is deprecated today.

Testing

There is no sandbox because there is nothing to break: the API and the MCP server are read-only, hold no accounts and change no data, so test against the live endpoints.