United Airlines Expert - the Ledger

This site records what is true about United Airlines, when it became true, when we learned it, and which source said so - quoted verbatim, with the hash of the page the quote came from. Nothing here is generated prose: every value on every card is a row a named source asserted, and every card shows you the sentence it was read out of.

Start here

• What changed at United - the change feed, newest first (RSS)
• A route card - announced, scheduled and as-flown side by side
• A policy card - the first checked bag, domestic, at the airport
• Every source and its cadence - worker health

For agents

The API is under /v1: /v1/facts/{subject}/{predicate} takes as_of (valid time), as_known_at (transaction time) and the predicate's identity fields as query parameters. A key with no version answers 200 with { "facts": [], "reason": "no accepted fact" }, never 404.

Look ids and enums up rather than guessing them. /v1/predicates is the closed catalog — every predicate with its subject type, identity fields and allowed values — and /v1/entities?q= resolves a name to a subject id. Together they are what makes a query like /v1/facts/policy:checked-bag-fee/policy.checked_bag_fee?market=transatlantic&bag_n=2&channel=airport constructible from the wire alone. An assistant that prefers tools can use the same five read-only tools over MCP at POST /mcp, which needs a bearer.