Show HN: Hermes – RyanAir price API with historical data

An unofficial REST API and MCP server called Hermes now exposes Ryanair flight prices with historical data, holding 87.1 million append-only fare observations across 5,278 active routes and 224 airports in 36 countries, according to its developer. Hermes offers six read-only MCP tools, including get_cheapest_fares, get_price_history and find_price_drops, and a free guest tier with no signup that provides 90 days of history per route and 120 list/detail plus 30 time-series requests per minute. The service is not endorsed by Ryanair, and its fares are observations rather than offers that must be confirmed on ryanair.com before booking.

Hermes · REST + MCP · free, no signup. Hermes is an unofficial REST API and MCP server mcp for Ryanair flight prices. Every observation is kept, so it knows what a fare cost last week. Ryanair’s own endpoints only know today. Swagger UI /docs/ · OpenAPI 3.1 /openapi.json · ReDoc /redoc/ · llms.txt /llms.txt Fare observations 87.1M append-only, never overwritten Active routes 5278 224 airports, 36 countries Requests served 99726 all-time, across every endpoint Last 24 hours 20257 hourly buckets, peak-normalised Point an AI assistant at Hermes and it answers flight questions for you. https://hermes.brinkhorst.dev/mcp claude mcp add --transport http hermes https://hermes.brinkhorst.dev/mcp Or any client that takes JSON config: { "mcpServers": { "hermes": { "type": "http", "url": "https://hermes.brinkhorst.dev/mcp" } } } Six read-only tools: get cheapest fares cheapest fare per day for a route get price history the observed price time series find price drops fares that just moved, network-wide explore destinations where can I go from here, cheapest first search airports / list routes network lookup Try: “is €60 a good price for Dublin to Barcelona in October?” curl https://hermes.brinkhorst.dev/api/v1/routes/DUB/BCN/cheapest curl "https://hermes.brinkhorst.dev/api/v1/anomalies/?kind=drop&limit=10" GET /api/v1/airports/ list airports filter by country, base GET /api/v1/routes/ list directed routes GET /api/v1/routes/{origin}/{destination}/cheapest GET /api/v1/routes/{origin}/{destination}/history price time series GET /api/v1/anomalies/ recent price drops and spikes GET /api/v1/explore?country=es cheapest destinations from a country Guest tier: no key, 90 days of history per route, the full 90-day look-ahead window, 120 list/detail and 30 time-series requests per minute. These URLs return a page to a browser, JSON to a client. Full lists: all 5278 routes /api/v1/routes/ , all 224 airports /api/v1/airports/ , latest price drops /api/v1/anomalies/ . Not a public one for fares. Ryanair's internal endpoints are undocumented and unstable; Hermes wraps them behind a versioned OpenAPI 3.1 /openapi.json contract. Yes — this one mcp . Streamable HTTP at /mcp , six read-only tools, no key required. No, and not endorsed by Ryanair. Fares are observations, not offers — confirm on ryanair.com before booking. Nothing, and no signup. Limits under guest tier guest-tier .