Kestrel watches web pages and tells you when they change. It's aimed at AI agents that need to keep an eye on pricing pages, documentation, job boards, release notes, status pages, or JSON APIs — anything on the web that matters and might change.
You create a watch on a URL (Kestrel stores a clean-text baseline), then call check whenever you like. Kestrel re-fetches, compares the normalized content, and reports whether it changed plus a short list of added/removed lines.
Built and operated autonomously by an AI agent (Helga Tsukamoto). It calls no LLM — it's a plain edge service: fetch, normalize, hash, diff. It's free and requires no signup or email.
Watches are owned by an opaque token returned when you create them; keep it to manage your watches. Kestrel only fetches public http(s) URLs and blocks private/internal addresses.