What's New digest builder

Turns the merged pull requests of one or more GitHub repositories into a human-readable "What's New" digest. You (the AI assistant) write the one-line summaries; a person reviews and commits the result. Runs locally against the GitHub API via gh. No server infrastructure.

This skill is repo-agnostic: point it at any repo(s) you can read with gh.

Prerequisites

• gh installed and authenticated (gh auth status).
• jq for shaping JSON (optional but convenient).
• Read access to the target repositories.

Inputs you need from the user

• repos — one or more owner/name slugs (e.g. octocat/hello-world).
• cutoff — how far back to look. Default: 90 days. Or an explicit ISO-8601 UTC start (e.g. a go-live date).
• output file — where the digest JSON should live (e.g. whats-new.json, or a site data file). Ask if not given.

Steps

1. Fetch merged PRs since the cutoff. For each repo, list PRs merged after the cutoff. Example (adjust --search window and --limit as needed):

   # Merged in the last 90 days:
   SINCE=$(date -u -d '90 days ago' +%Y-%m-%d 2>/dev/null || date -u -v-90d +%Y-%m-%d)
   gh pr list --repo <owner/name> --state merged --limit 200 \
     --search "merged:>=$SINCE" \
     --json number,title,body,mergedAt,url,labels,author \
     > /tmp/whats-new-<repo>.json
   

   For an explicit cutoff, set SINCE to the ISO date directly. Repeat per repo and concatenate. Note any repo that was empty or unreachable.

2. Deduplicate against any existing digest. If the output file already exists, load it and skip PRs whose id (use repo#number or the PR URL) is already present — never re-summarize an entry that's already written, so reviewed wording stays put. Idempotency is the point.

3. Summarize each new PR. For every PR produce { "id", "repo", "category", "title", "summary", "mergedAt", "url" }:

   • category ∈ Feature | Fix | Performance | Docs | Maintenance. Use the conventional-commit prefix in the title as a hint (feat→Feature, fix→Fix, perf→Performance, docs→Docs; chore/refactor/build/ci/test/style→Maintenance), but reclassify from the actual PR body when that's clearer.
   • summary: ONE plain-language sentence describing the change and, where possible, its value to a user of the project. Strip issue numbers, internal ticket refs, deploy/CI mechanics, and jargon. Write in an approachable, community voice.
   • title: keep the PR title, or supply a cleaner display title.

4. Write the digest. Merge the new entries into the output file (append to the existing array, keep it sorted newest-first by mergedAt). Write valid JSON; don't reorder or reword existing entries.

5. Report to the user: how many new entries were added, from which repos, and covering which date range. Remind them to review the output file and commit it. This skill does not deploy or publish — it only produces the data.

Notes

• Idempotent: PRs already in the file are never re-summarized.
• Windows: if /tmp isn't writable, use a temp dir you can write to.
• Private/enterprise repos: work fine as long as gh is authenticated for them; the digest content is only as public as you choose to publish it.
• Adapt the schema to your target. If you're feeding a static-site data file or a CHANGELOG, map the fields above onto that format in step 4.