LetsFG — Flights & Hotels
Search and book flights and hotels: hundreds of airlines, plus bookable hotel rates.
Computer or cloud
Airfare Brain
Overview
Description from the maker (original English)
True cost of flight extras (bags, seats, fees) on 29 airlines in Europe and North America, sourced.
PopNx MCP’s three pillars
These three are never merged into one score: opinions, measurements and popularity are different things.
- User voiceiNo reviews yetReviews open together with accounts in a later step
- Our basic checksi4 of 4 passedChecked from public information; code not scanned yet
- UsageiEarly★ 0
What you can do with it
We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.
- Connection: Runs in the cloud
- Transport: Streamable HTTP
- Category: Travel, maps & weather
Install
Pick the AI app you use, then copy the settings.
Before you install
- Basic checks: 4 of 4 passed
- Runs on the maker’s server: what you ask it goes through their server.
- Can do 5 things (tools) get_capabilities, list_airlines, airline_fees, true_cost …
- The registry lists no key to fill in.
You need
- Runs in the cloudNothing to install; it connects over the internet
Which app do you use?
Pick your app above. We remember it, so next time the button says “Install in …”.
Works in Claude on the web, desktop and mobile:
- Open Settings → Connectors
- Press Add custom connector
- Paste the address below and press Add
- If it asks you to sign in, sign in with the maker
https://airfarebrain.com/mcpRun this in your terminal
claude mcp add --transport http airfare-brain https://airfarebrain.com/mcpOr copy the settings yourself
Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"airfare-brain": {
"url": "https://airfarebrain.com/mcp"
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
Or copy the settings yourself
Paste into .vscode/mcp.json in your project
{
"servers": {
"airfare-brain": {
"type": "http",
"url": "https://airfarebrain.com/mcp"
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
ChatGPT connects only to servers on the internet:
- Open ChatGPT on the web → Settings → Connectors (Apps)
- Press Create or Add (some plans need Developer mode under Advanced first)
- Paste the address below, give it a name and save
- If it asks you to sign in, sign in with the maker
https://airfarebrain.com/mcpMenu names can differ slightly by plan and over time.
Your choice stays on this device in a cookie; no account needed.
These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.
What it can do
Tool names and descriptions exactly as the server reported them on Nov 7, 2026. The maker wrote them, not us; we show them as plain text.
get_capabilitiesWhat Airfare Brain covers: airlines, how fees are researched and dated, what it does NOT do (no live fares, no booking), and what car hire at the destination airport typically costs.
list_airlinesList every airline with a fee table: name, IATA code, the date its fees were checked, and its page.
airline_feesOne airline's published extra fees (bags, seats, priority, check-in, changes, payment), each with the price range, when bought (at booking / later / airport), how it is charged, its source URL and the date checked. Optionally filter by category.
true_costThe true cost of a flight on one airline. Pass `fare` (the total for the whole party, from a flight-search tool or the person) to get fare + extras; without it you get the extras alone. Extras = what the person chooses (cabin bag, checked bag by kg, seat, priority, infants) for t
trip_at_airportThe whole trip into one airport in one answer: the flight's extras on an airline (bags, seats, fees, as true_cost) AND what car hire there really costs (Car Rental Brain's measured median per day, car only, dated). Use for 'flying to Faro with Ryanair, bags and a hire car: what w
Basic checksi
We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 10, 2026
- ✓ Pass
Maker matches the repo
The registry name was verified against the domain airfarebrain.com (the registry checks domain ownership)
- ✓ Pass
Still maintained
Code last changed 4 days ago
- … Not checked yet
Has a licence
We have not read this repo from GitHub yet
- ✓ Pass
Endpoint responds
Responded in 136 ms (HTTP 200)
- – Not applicable
Sign-in with OAuth
No sign-in needed
- ✓ Pass
No hidden instructions in tool descriptions
Read 5 tool descriptions and found no hidden instructions to the AI
Compared with others in Travel, maps & weatheri
- More stars than 0% of the other 1794 servers in this category
- Published to the registry more recently than 70% of the other 1794 servers in this category
- Basic checks equal to or better than 100% of the other 1794 servers in this category
Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.
Common questions
Is Airfare Brain safe?
It passed 4 of 4 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.
What keys or codes does it need?
The registry does not list a required key, though some servers ask you to sign in on first use.
Does it run on my computer or in the cloud?
It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.
Is it still maintained?
The GitHub repo last changed 4 days ago, and the latest version (1.0.6) reached the registry 12 days ago.
Which apps can use it?
Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.
What can I use instead?
In the same category: LetsFG — Flights & Hotels, Google Maps MCP Server, Mu
Alternatives
Servers in the same category from other makers, sorted by stars.
Reading a card:↓ Downloads per weeki★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi
Google Maps MCP Server
18 Google Maps tools for AI agents — geocode, search, directions, weather, and more.
Runs on your computer
Mu
News, web search, mail, markets, weather, places, files, calendar, contacts. 67 tools, one endpoint.
Runs in the cloud✓ micro.mu
README from the maker
Open the README
Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.
Airfare Brain MCP server
The true cost of a flight, for AI assistants. Bags, seats, priority boarding, check-in and payment fees on 32 airlines (Ryanair, easyJet, Wizz Air, Jet2, British Airways, Lufthansa, KLM, Air France, Iberia, Turkish, Finnair, SAS, Swiss, Austrian, Delta, United, Southwest, JetBlue and more), each price taken from the airline's own pages, with the source and the date it was checked.
Free. No API key. No login. Read-only.
MCP endpoint (streamable HTTP):
https://airfarebrain.com/mcpListed in the official MCP Registry as com.airfarebrain/airfare-brain, in ChatGPT's plugin directory and in Claude's connector directory. Website: airfarebrain.com · Fee data: airfarebrain.com/fees · For AI: llms.txt
Why it exists
The fare a flight search shows is not what the trip costs. A cabin bag, a checked bag, a seat next to someone you know, checking in at the airport or paying by card can each add more than the fare itself, and the price goes up if you add them later or at the airport. Airfare Brain reads each airline's published fee pages, records every price with its source and date, and answers with the numbers, so an assistant can say what a flight will really cost.
Tools
| Tool | What it answers |
|---|---|
get_capabilities | What is covered, how fees are researched and dated, what it does not do (no live fares, no booking) |
list_airlines | Every airline with a fee table: name, IATA code, the date its fees were checked, its page |
airline_fees | One airline's extras (bags, seats, priority, check-in, changes, payment): price range, when bought (at booking / later / at the airport), source URL, date checked |
true_cost | Fare + the extras the person chooses, for the whole party and each flight, with what it costs if added later or at the airport |
trip_at_airport | The whole trip into one airport: the flight's extras on an airline AND what car hire there really costs (Car Rental Brain's measured median per day), dated and linked |
Ranges are shown exactly as the airline publishes them. A fee the airline does not publish is said to be unknown, never counted as free. Figures from a third party (only where the airline publishes none) are labelled "reported".
Example questions
- "I found a Ryanair flight for €39. What will it cost with a cabin bag and a 20kg bag, return?"
- "Is easyJet or Wizz Air cheaper for two people with one checked bag between them?"
- "What does Jet2 charge to choose a seat?"
- "How much more is a bag at the airport than online on Wizz Air?"
- "Does British Airways' Basic fare include a cabin bag?"
- "Flying Ryanair into Malaga for a week with a 20kg bag and a hire car: what will it all cost?"
Connect
Claude (claude.ai / Claude Desktop)
Settings → Connectors → Add custom connector → URL https://airfarebrain.com/mcp.
Or in claude_desktop_config.json:
{"mcpServers": { "airfare-brain": { "url": "https://airfarebrain.com/mcp" } } }
</details>Claude Code (plugin)
/plugin marketplace add jimiwalters-cmyk/airfare-brain-mcp/plugin install airfare-brain@airfare-brain
Or add the server directly: claude mcp add --transport http airfare-brain https://airfarebrain.com/mcp
ChatGPT
Add the Airfare Brain plugin from ChatGPT's plugin directory. Or: Settings → Apps & Connectors → Advanced → Developer mode → Create → MCP server URL https://airfarebrain.com/mcp, authentication: none.
Cursor / Windsurf / Cline / VS Code
{"mcpServers": { "airfare-brain": { "url": "https://airfarebrain.com/mcp" } } }
</details>Stdio-only clients
npx mcp-remote https://airfarebrain.com/mcpPlain JSON
All fee tables in one file: airfarebrain.com/data/fees.json.
How the numbers are made
Each airline's fee pages are read by hand, every value is stored with the page it came from, a short quote and the date, and each table is re-checked monthly (a table past its re-check date is flagged on the site). Travellers can report what they actually paid; those reports are checked against the tables.
Fee pages
The same data as web pages, one per airline (checked bag, cabin bag, seats, with the date and the airline's own source):
Aer Lingus · Air Canada · Air France · Alaska Airlines · American Airlines · Austrian Airlines · British Airways · Delta Air Lines · easyJet · Eurowings · Finnair · Frontier Airlines · Iberia · Jet2 · JetBlue · KLM · Lufthansa · Norwegian · Pegasus · Ryanair · SAS · Southwest Airlines · Swiss · TAP Air Portugal · Transavia · Turkish Airlines · United Airlines · Virgin Atlantic · Volotea · Vueling · WestJet · Wizz Air
Compare all airlines: checked bags · cabin bags · seats. Booking through Kiwi.com: what it adds to bag prices. Flights into 124 airports with the true cost and car hire there.
Sister tool
For car hire at the airport you land at: Car Rental Brain (https://app.carrentalbrain.com/mcp).
Affiliate disclosure
The MCP tools return fee data only, with no booking links. The airfarebrain.com website's flight search links to Kiwi.com through its affiliate programme, and Airfare Brain may earn a small commission at no cost to the person booking.
Privacy
The tools take no personal data and need no account. Privacy policy: airfarebrain.com/privacy.
Contact
hello@airfarebrain.com