FlightAware and Amadeus are the two providers the Flights tag page ranks first, at 59.1 and 57.1 on the Kin Score, both strong, 2.0 points apart. The Kin Score measures the public API surface, not the product and not the company. In a tag of 42 providers whose scored members average 21.5, both sit more than 35 points above their own category, and Amadeus wins four of the six facets. The question a buyer has is simpler than the table: both of these say flights, so which one do I build on? In November 2026 the answer turns on a fact the score does not yet carry. The Amadeus catalog record notes that the Self-Service developer portal was scheduled to be decommissioned on 17 July 2026. On the day of writing, test.api.amadeus.com, the base URL every one of its 28 API pages declares, no longer resolves in DNS, and the Amadeus OpenAPI repository on GitHub is archived, last pushed in September 2024. The production host still answers. The self-service surface this score was built from is going or gone.
The business. These are two different purchases that meet at one word. FlightAware sells flight data: real-time tracking assembled from air traffic control feeds, radar, ADS-B and satellite, exposed through AeroAPI, a query-based REST API, and Firehose, a streaming feed of position and event messages for enterprise customers. Amadeus is the technology provider behind much of the travel industry, and Amadeus for Developers was its self-service door, with 40+ REST APIs across flights, hotels, destination content, cars and transfers, market insights and prediction services, a free, capped Test environment and a paid Production one. Access is where they diverge most. FlightAware’s record reads freemium with self-serve signup and a try-now surface, authenticated by API key, with 5 plans and 6 rate-limit entries recorded. Amadeus reads paid, onboarding unknown, no trial, OAuth 2.0 client credentials, 1 plans record and 3 rate-limit entries. Enterprise customers, the record says, keep access through the equivalent Enterprise APIs, and those are not the APIs on these pages.
The APIs. FlightAware declares one API and publishes 10 API pages, because the catalog splits AeroAPI by resource, so read the pages as resources. The Airports API carries 17 operations, the Flights API 11 and the Operators API 8, with Foresight for the predictive models, Alerts for push on flight events, and Firehose as the one AsyncAPI. Amadeus declares 40 and publishes 28 pages, most of them one operation each: Flight Delay Prediction, Airport Ontime Prediction, Checkin Links and Display SeatMaps, with the Booking API at 6 operations the largest. The artifact counts are not comparable at face value. Amadeus’s page carries 18 Arazzo workflows, 106 collections, 810 JSON Schemas and 565 examples against none of those for FlightAware, and the sheet records 0.0 first-party catalog points for Amadeus against 24.0 for FlightAware. The 18 workflows carry no first-party provenance marker and do not appear in Amadeus’s own specification repository, so read them as catalog work, not as something Amadeus ships. Both agentic-access profiles are derived by us, and so are FlightAware’s 4 agent skills. The number that matters most is callability. All 8 FlightAware contracts resolve to a live host. 2 of 28 Amadeus contracts do, 7.1 percent, which is the DNS fact above expressed as a measurement.
The experience, facet by facet. Amadeus takes discoverability 71.4 to 57.1, contract quality 62.1 to 57.1, contract governance 27.3 to 4.5, and developer ergonomics 85.7 to 47.0. Those four facets carry 0.67 of the weight. FlightAware takes operational transparency 84.2 to 23.7 and access clarity 84.2 to 44.7, at weights of 0.13 and 0.20. Those are the two widest gaps on the sheet, 60.5 and 39.5 points, and together they are worth about 15.8 on the composite against about 13.2 for Amadeus’s four wins, which is how FlightAware leads the six-facet base 57.7 to 55.1. The conditional layers then move FlightAware up 1.4 and Amadeus up 2.0, both under the same Horizontal regulatory regime, and the upsert facet is absent on both because the rubric found no parseable contract for it on either side, which leaves the 2.0 on the page. In plain words, Amadeus is easier to start with, with SDKs in several languages, a public Postman workspace and a richer contract, and FlightAware tells you more about how the API behaves and what it costs, with published plans, stated limits and a security posture the catalog can read. The 4.5 on governance is FlightAware’s weakest number, and it means no ruleset, no vocabulary and no declared conformance.
Agent readiness follows the base rather than the ergonomics. FlightAware scores 32.2 and is agent-ready. Amadeus scores 27.6 and is agent-aware, under the 28.6 floor for the band above. The band is gated rather than read off the score, so the 4.6-point gap matters less than the dimensions behind it. FlightAware’s contract carries verified examples where Amadeus’s are partial, and its event surface is described, which is Firehose. Amadeus wins one: its error semantics are verified where FlightAware’s are derived. Neither has an MCP server, an agent card, idempotency keys, a dry-run mode or any of the four identity dimensions, and both document rate limits. FlightAware’s agent skills are derived, so that dimension lit on work we did.
The verdict. If you need to know where an aircraft is, was or will be, FlightAware is the only one of these with that surface, and you can sign up, read the price and call it today. If you need to shop and book a trip, Amadeus is the only one with that surface, and the self-service road to it is closed. The Enterprise APIs the record points to are a sales conversation, not a developer portal. The 2.0 points between them are real, and they are last quarter’s. The honest reading of this page is that the Flights tag ranks a decommissioned program second and the catalog has not caught up, so we are filing the dead test host and the archived repository against the Amadeus record for the next rescore to read the surface as it is. FlightAware’s path is governance, a ruleset and a vocabulary that would move its 4.5, and an idempotency key on alert writes, which is what moves agent readiness toward agent-native. Amadeus’s path, for whatever Amadeus publishes next, is the one every decommission creates: say where the APIs went.