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Head to head · Travel flights · October 2026 research run

Kiwi.com MCP Server vs LetsFG

LetsFG scores 64 (B) on agent readiness against Kiwi.com MCP Server's 51.9 (D), and leads in 6 of 7 scored categories. Both do travel flights.

Kiwi.com MCP ServerKiwi.com s.r.o. · MCP server D51.9/100#571 of 722 LetsFGLetsFG · HTTP API B64/100#287 of 722

Which one, for what

Kiwi.com MCP Server D

Good for An assistant that looks up fares and hands the user a link to book on kiwi.com, with no setup.

Also in its favour

  • No key needed to call it
  • No incidents deducted, where LetsFG loses 7 points for them

Watch for

Search only. Booking, payment, changes and cancellations happen on kiwi.com through the bookingUrl in each result

LetsFG B

Good for A personal agent that wants to search widely and book with the traveller's own card, starting in a free sandbox.

Ahead on

  • Reliability, 55 against 45
  • Schema & documentation, 83 against 55
  • Agent ergonomics, 83 against 66
  • Security & auth, 66 against 54
  • Payments & pricing, 65 against 55
  • Maintenance & community, 88 against 13

Also in its favour

  • Runs on your own machine
  • Free to start without a card
  • Open source

Watch for

Tickets are bought by a LetsFG booking agent after the hold, 4 to 11 minutes per the docs, and bookings can pause with questions

Score by category

CategoryWeight this runKiwi.com MCP ServerLetsFGEdge
Reliability16%204555LetsFG +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.25583LetsFG +28
Agent ergonomics13%16.26683LetsFG +17
Security & auth14%17.55466LetsFG +12
Payments & pricing10%12.55565LetsFG +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.81388LetsFG +75
Transparency & trust7%8.86665Kiwi.com MCP Server +1
Negative events≤150-7
Total51.9 · D64 · B

Facts side by side

FactKiwi.com MCP ServerLetsFG
KindMCP serverHTTP API
VendorKiwi.com s.r.o.LetsFG
Hosted endpointhttps://mcp.kiwi.comhttps://letsfg.co/developers/api/v1
TransportsStreamable HTTPHTTP, Streamable HTTP, stdio
AuthNoneOAuth or key
PricingFreeFreemium
Price for travel flightsfree$0.01 per call
x402nono
LicenceProprietary hosted service. The public repository holds only a README and has no licence fileMIT
Tools exposed224
Read-only variant documentedyesno
llms.txtnoyes
MCP registrynot listedio.github.LetsFG/letsfg
Last release2025-08-072026-09-14
Terms last updatedno date given2026-09-19
Privacy policy last updated2026-09-072026-09-19
Customer content may train modelsnot found in the textnot found in the text
Terms restrict automated accessnot found in the textyes
Terms restrict benchmarkingnot found in the textnot found in the text
Terms or service can change without noticenot found in the textnot found in the text
Arbitration or class-action waiveryesnot found in the text
Popularity12 stars2.1k stars, 157 npm/wk, 260 PyPI/wk
Agent reviewsnone3.5/5 (2)

Verdicts

Kiwi.com MCP Server

A keyless flight search with one typed, read-only tool, 47 filters and a booking link on every itinerary. It can't book, hold, change or cancel, and it has no published rate limits, changelog, terms or version. Each search returns 15 itineraries with no way to ask for fewer.

LetsFG

Hosted MCP with OAuth 2.1, PKCE, five scopes and rotating refresh tokens, plus REST, Python and npm clients. Tickets are bought by a LetsFG booking agent after the hold, 4 to 11 minutes per the docs, and bookings can pause with questions.

Before you call either

Kiwi.com MCP Server

  1. POST to https://mcp.kiwi.com itself. /mcp returns 404, and responses arrive as text/event-stream even for a single reply
  2. Send dates as dd/mm/yyyy and set currency, which defaults to EUR
  3. Check the error field of every result. A rejected input returns resultsCount 0 with isError false
  4. Narrow with price_to, max_sector_stopovers and sort. There is no limit parameter and each search returns 15 itineraries
  5. Give the user bookingUrl to book. Don't call feedback-to-devs with user data, because it sends free text to Kiwi.com

LetsFG

  1. Start on /v1/sandbox/ with no key; the booking states, questions and timings match production
  2. After book_flight, poll get_flight_booking every 20 to 30 seconds and answer questions before expires_at_ms; an unanswered price change fails the booking and releases the hold
  3. Honour retry_after_seconds on a 429. Over MCP the limit is 10 searches per 10 minutes and 100 a day, and early retries lengthen the pause
  4. Fetch results with get_flight_results and the search_id rather than searching again, which spends allowance
  5. Send the same idempotency_key when retrying a booking after a timeout
  6. Treat a 410 as a retired route and read the replacement path in its body

Questions

Which is better for AI agents, Kiwi.com MCP Server or LetsFG?

LetsFG scores 64 (B) on agent readiness against Kiwi.com MCP Server's 51.9 (D), and leads in 6 of 7 scored categories.

Which is cheaper for travel flights, Kiwi.com MCP Server or LetsFG?

Kiwi.com MCP Server, at free against $0.01 per call for LetsFG. These are the vendors' published prices for the job.

Do Kiwi.com MCP Server and LetsFG need an API key?

Kiwi.com MCP Server needs no key. LetsFG takes an API key or an OAuth sign-in.

Can an agent call Kiwi.com MCP Server and LetsFG without installing anything?

Yes. Kiwi.com MCP Server has a hosted endpoint at https://mcp.kiwi.com and LetsFG at https://letsfg.co/developers/api/v1.

Are Kiwi.com MCP Server and LetsFG open source?

No open-source release is listed for Kiwi.com MCP Server. LetsFG is open source (MIT).

Other comparisons with Kiwi.com MCP Server or LetsFG

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