Start Day

Produce a short morning brief: what happened since the user was last active, and 2–8 ranked things to do today. Discovery-driven — no hardcoded sources. Read-only; never posts, commits, or mutates anything.

1. Compute the lookback window

A since:<date|weekday> argument overrides everything below.

Two inputs, combined:

• fixed_floor — the minimum lookback. The last business day at 15:00 local (17:00 assumed end-of-day, minus 2h). Last business day: Mon → previous Fri; Sat/Sun → previous Fri; else → yesterday.
• empirical — extends the window earlier only. The end of the user's last genuinely active day: the later of (a) the newest local session under ~/.claude/projects/*/*.jsonl dated before today, and (b) the user's last Slack message (from:me sort:timestamp).

window_start = the earlier of fixed_floor and empirical. Empirical can only push earlier — a low-focus weekend glance cannot shrink the window below fixed_floor, and a vacation gap extends it. window_end = now.

Compute fixed_floor (macOS date):

case $(date +%u) in 1) back=3;; 7) back=2;; *) back=1;; esac   # Mon→Fri, Sun→Fri, else yesterday (Sat→Fri via back=1)
floor=$(date -v-${back}d -v15H -v0M -v0S +%s)                  # last business day @ 15:00 local

Holidays need no special handling: if the last business day was a holiday, the user's empirical last-active day predates it and extends the window automatically.

2. Discover and run summarization skills

Scan the available skills. Run every skill whose name matches summarize-* OR whose description declares summary / recap / status intent. Do not hardcode which ones — discover them so newly added ones are picked up. Pass the window when a skill accepts a range. If none exist, skip this step.

3. Run local extensions

Run every available skill whose name matches start-day-* (there may be several). Machine- and context-specific morning setup lives there, outside this portable skill. Fold each extension's output into the brief as bullets.

4. Slack catch-up (read-only, consent-gated)

Slack search reaches DMs and private channels, so ask once before searching: "Scan Slack DMs/private channels for saved items and pings since <window_start>?" On yes:

• Saved / "Later" list: Slack:slack_search_public_and_private with query is:saved.
• Pings since the window: query to:me, after:<window_start unix ts>, sort:timestamp.
• OOO garnish: Slack:slack_read_user_profile — note if the user is currently OOO; deprioritize pings from colleagues whose status shows OOO.

Reminders are not reachable through the Slack API — skip them. Never send or post anything (per no-post-without-confirmation).

5. Synthesize the brief

Open with the window and an override hint:

Caught up since Fri Jun 19, 3:00pm (~3d). Override: /start-day since:monday.

Then 2–8 ranked items, sampled across size — a couple of quick wins to start the day, 1–2 big-rocks to advance a major project, plus anything time-sensitive from Slack. Tag each [quick] / [project] / [slack]. One terse line each, leading with the action.

Brief only: no auto-actions, no backlog writes, no posting. Stay independent of any tracker — when run inside a tool that supplies project context (system prompt, discovered skills), use it, but never depend on it.