Test endpoints that misbehave — and the well-formed counterparts that don't.
catastrophic.io documents three coordinated endpoint hosts: a chaos surface, a well-formed control surface that mirrors it, and a host that serves chaotic versions of the canonical well-known files crawlers and agents fetch automatically. Point your client, crawler, scanner, or AI agent at any of them and observe how it copes with HTTP responses that lie, contradict themselves, or arrive in the wrong shape.
Every endpoint is free, public, no signup, and rate-limited at 60 requests per minute per IP (a few unbounded-URL endpoints have a tighter 10/min cap). No request bodies, headers, or query parameters are logged or retained.
Three sites, one purpose.
Chaos
HTTP endpoints that misbehave on purpose. Latency, lying status codes, broken bodies, contradictory headers, intermittent failures, and other adversity your client should handle gracefully (but probably doesn't).
Control
Well-formed counterparts to every chaos and bot-file endpoint, served at the same paths. Build your client against not, then flip the hostname to test how it handles adversity — same code, opposite behavior. Also includes an unbounded-URL fixture for crawler and cache-pipeline stress testing.
Bot files
Chaotic versions of the canonical-path files that crawlers, scanners, and AI agents fetch automatically — robots.txt, llms.txt, sitemap.xml, security.txt, AASA, and the rest. Each at its real well-known path.