catchup

Two modes. `$ARGUMENTS` containing `handoff` → write the handoff note (end of session). Anything else → catch up (start of session), treating any remaining arguments as a focus area. ## Catch up (default) Rebuild context in four steps, cheapest first. Read; never modify anything. 1. **Handoff note**: if `.claude/HANDOFF.md` exists, read it first — it's the previous session's intent and beats anything inferable from git. Note its date; flag if it predates the latest commit (it may be stale). 2. **Branch state** — live snapshot injected below (git output as of this session's start; no need to re-run these three): ```! BASE=$(git merge-base HEAD origin/HEAD 2>/dev/null || echo HEAD~10) echo "### git status (uncommitted/staged work in flight)" git status --short 2>/dev/null || echo "(not a git repo)" echo echo "### git log --oneline ${BASE}..HEAD (what this branch did)" git log --oneline "${BASE}..HEAD" 2>/dev/null || echo "(no divergence from base)" echo echo "### git diff --stat ${BASE}..HEAD (where the change mass is)" git diff --stat "${BASE}..HEAD" 2>/dev/null || echo "(no diff vs base)" ``` 3. **Read the changed files** — the diff hunks, not whole files. If more than ~15 files changed, read the 5 with the most churn plus anything matching the focus area, and list the rest by name. 4. **Summarize** in this shape, terse: ``` ## Catchup: <branch> **Goal** (from handoff or inferred): <one line> **Done**: <commits/changes, 2-4 bullets> **In flight**: <uncommitted work, or "clean"> **Next** (from handoff, or inferred): <one line> **Watch out**: <gotchas from the handoff, if any> ``` If there's no handoff note and no branch divergence (fresh clone, main at origin), say so and ask what to work on instead of inventing a summary. ## Handoff (when `$ARGUMENTS` contains `handoff`) Write `.claude/HANDOFF.md` capturing THIS session for the next one. Keep it under 30 lines — it's a note, not a transcript: ```markdown # Handoff — <date> — <branch> ## Goal <what this work is trying to achieve, one line> ## State - Done: <completed + verified> - In flight: <started, not finished — exact file/function> - Untouched: <known remaining scope> ## Gotchas - <what failed and why, dead ends not to repeat, surprising constraints> ## Next step <the single concrete action to take first> ``` Show the note and confirm before writing. Overwrite any existing note (it described an older state). Suggest adding `.claude/HANDOFF.md` to `.gitignore` if it isn't there — it's personal session state, like `CLAUDE.local.md`. ## Rules - Catchup mode is strictly read-only. - Never paste large diffs into the summary — reference `file:line` and characterize. - The handoff captures decisions and dead ends, not narrative. "Tried X, broke Y, use Z instead" is the gold standard line.