George Giosue
ESEN
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MCP Emtrafesa

Written on 3 min readDemonpm

An MCP server that gives AI assistants structured access to Emtrafesa’s intercity transport data: terminals, routes, schedules, seat availability and already-purchased tickets.

Since August 2026 it runs as a remote server on Cloudflare Workers. No install, no authentication: paste the URL into your client.

Connect

In Claude Desktop or claude.ai, Settings → Connectors → Add custom connector:

https://mcp-emtrafesa.georgegiosue.dev/mcp

In Claude Code:

claude mcp add --transport http emtrafesa https://mcp-emtrafesa.georgegiosue.dev/mcp

It is still published on npm for anyone who prefers to run it locally over stdio.

Tools

Tool What it does
get-terminals Every Emtrafesa terminal in Peru
get-arrival-terminals Destinations available from a city
get-departure-schedules Departures between two cities
get-available-seats Free seats on a specific departure
get-latest-purchased-tickets Purchased tickets, by national ID and email
get-ticket-pdf A ticket as a PDF
get-frequently-asked-questions Luggage, minors, senior passengers, service rules

Every field the tools return is self-describing, so the model reads the results without extra explanation. You ask by city name; omitting the date means today in Peru.

Architecture

The server is built from a single createServer() factory that both entry points share: serveStdio() for the npm package and createMcpHandler() for the Worker. Tools are defined once and served over both transports.

Three things about the Workers deployment were not obvious:

  • SDK v2 exposes a workerd export condition that swaps Ajv for a compatible validator. Ajv uses eval, which the Workers runtime forbids.
  • cheerio’s main entry pulls in undici and parse5-parser-stream, which depend on net and tls. The cheerio/slim variant avoids both.
  • The bundle needs nodejs_compat for the Buffer used by PDF generation.

Tech

TypeScript, Bun, Model Context Protocol SDK v2, Cloudflare Workers, Zod, Cheerio.

Screenshots

Ticket lookup as PDF

Ticket lookup as PDF

Motivation

To standardize programmatic access to transport data for agent integrations and trip-planning flows. Moving to a remote server removed the last of the friction: you no longer need Node installed or a config file edited to use it.