I built a prototype to classify API deprecations. Here's what I learned.

I went looking for a tool that would tell me specifically when an API I depend on is being deprecated — not every changelog entry, just the ones that mean "you need to do something before this date or something breaks." It didn't exist in the way I wanted, so I built a proof of concept to see if the problem was solvable. The problem with existing approaches The obvious workaround is subscribing to vendor mailing lists. The issue: when you depend on 10+ external APIs, you end up with 10 different newsletters. Breaking changes share an inbox with patch notes, SDK releases, and marketing fluff. What the prototype does I wrote a script that fetches changelogs concurrently, then passes the content to an LLM to identify deprecations and ignore everything else. The classification works. "gpt-4-turbo is being deprecated" comes out labeled correctly. "We added an optional field" gets ignored. The hardest part is the parsing layer - Stripe uses structured JSON, but others use unstructured blog p