Monthly is fine, but not monthly all at once, because I watch multiple pages on one website, and that triggers the rate limiting.

The ideal pipeline for me would be "notice a change in a specific part of a page, use a very small LLM to extract a value or answer a question, update a constant in a file and make a pull request".

I've been thinking about this pipeline for a long time because my work depends on it, but nothing like it seems to exist yet. I'll probably write my own, but I just can't find the time.

You can already work around the rate-limit issue today — there's a global minimum recheck interval in Settings that spreads checks out across time. Not per-site throttling yet, but it prevents one domain from getting hit too many times at once.

The pipeline you described — detect a change, extract a value with a small LLM, open a PR — is pretty much exactly what the MCP server is designed for. Connect Site Spy to Claude or Cursor, and when a specific part of a page changes, the agent can handle the extraction and PR automatically. I don't think anyone has wired up that exact flow yet, but all the pieces exist.