Blogwatcher

Overview

Blogwatcher checks a list of URLs at every heartbeat for new content. It stores a content hash per URL in a state file and reports changes since the last check.

Configuration

Blogs to watch are listed in skills/blogwatcher/blogs.md in the workspace. Format — one URL per line, optional label after a space:

https://example.com/blog        Example Blog
https://news.ycombinator.com    Hacker News

Blank lines and lines starting with # are ignored.

State file

State is stored in skills/blogwatcher/state.json in the workspace. Format:

{
  "https://example.com/blog": {
    "last_checked": "2026-01-01T12:00:00",
    "content_hash": "a1b2c3d4"
  }
}

Steps (manual trigger or heartbeat)

1. Read config — read skills/blogwatcher/blogs.md. If the file does not exist, reply with setup instructions (see Setup below).

2. Read state — read skills/blogwatcher/state.json. If missing, start with an empty state object {}.

3. Check each URL — for each URL in blogs.md: a. web_fetch the URL. b. Compute a short hash: take the first 4000 characters, count words, build a fingerprint string len:<chars>|words:<n>|head:<first100chars>. c. Compare with stored hash. d. Mark as new if hash differs or URL is not in state yet.

4. Write state — update last_checked and content_hash for every checked URL, then write skills/blogwatcher/state.json.

5. Report:

   • If new content found → list each changed URL with label and a 1-sentence summary of what changed.
   • If nothing changed → reply HEARTBEAT_OK (heartbeat mode) or "No new content since last check." (manual).
   • If a URL could not be fetched → note it but continue with the others.

Heartbeat

On every heartbeat run, execute the full Steps 1–5 above silently. Only send a message to the user when at least one URL has new content. Otherwise reply HEARTBEAT_OK.

Setup instructions (when blogs.md is missing)

Reply: "Blogwatcher is not configured yet. Please create skills/blogwatcher/blogs.md in your workspace and add one URL per line:

https://your-blog.com/feed     My Blog
https://example.com/news       Example News

Then trigger blogwatcher again or wait for the next heartbeat."