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Trvl
Travel MCP server + CLI for AI assistants — flights, hotels, trains, cars, ferries, price alerts. No API keys, single Go binary. 1 smart MCP tool + 66 aliases (98.9% smaller…
Install
$
claude mcp add trvl --transport stdio -- trvl mcpInstall command taken from the project's README or registry entry. Always review code before running it.
README excerpt
Read full README on GitHub →trvl — Real travel search for your AI assistant
Ask your AI assistant to plan a real trip, and it actually can. trvl gives Claude, Cursor, Windsurf, Codex, or any MCP-compatible client one smart tool — the travel router — with live access to flights, hotels, rental cars, trains, buses, ferries, price alerts, award sweet spots, weather, and destination intel. Free for noncommercial use, no personal API keys for default search, no signup. One binary.
You: I have €300 and a free weekend. Surprise me.
Illustrative response shape (prices are examples): Dubrovnik, Croatia 🇭🇷 — ✈️ Ryanair HEL→DBV €167 RT · 🏨 Old Town Studios 4.6★ €84 · 🌡️ 26°C, sunny. 📊 Naive €350 → optimized €251 → saved €99 (28%) by flying Friday and splitting airlines.
▶ Try it live, no install: socialistic.ai/trvl-travel-mcp (community-hosted).
How it works, in one paragraph
trvl is a single binary that runs on your machine. Your AI client talks to it over MCP; it queries flight, hotel, transport, weather, and places sources, then merges, de-duplicates and optimizes the results before handing back one answer. Most sources are free public endpoints, so there is nothing to sign up for. The ones behind bot protection may reuse the browser session you already have, which is the one thing worth reading about before you install: see What trvl reads, and what it keeps.
trvl speaks the two latest MCP revisions: 2026-07-28 and 2025-11-25. An initialize with no _meta is answered as 2025-11-25, whether the handshake names 2025-11-25 or 2026-07-28, and that answer includes ping and resources/subscribe. _meta of 2026-07-28 on an initialize selects the 2026 shape. A client that sends 2026-07-28 in _meta["io.modelcontextprotocol/protocolVersion"] on each request gets server/discover, resultType, cache hints on the list and read endpoints, and subscriptions/listen instead of resource subscribe. Any other _meta protocol version returns JSON-RPC -32022 with data.supported and data.requested. On HTTP the MCP-Protocol-Version header has to match that field; a 2026 header alone is -32020. A 2026 request must also send Mcp-Method (and Mcp-Name for tools/call, resources/read, and prompts/get).
Why trvl, not the alternatives
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