throughline — Onboard (orientation)

Goal: Load everything needed to resume work without re-deriving solved problems. The SessionStart hook already injects a lightweight pointer + git state; this skill is the full pass when you want depth.

Data directory: $THROUGHLINE_DATA_DIR if set, else <project-root>/.claude/throughline/. Below, DATA refers to that path. In a linked git worktree, <project-root> here is the main working tree, not the worktree itself (see README "Git worktrees") - so DATA is shared across every worktree of the repo.

Phase 1: Load durable context

1. Read DATA/HANDOFF.md in full. If absent, note the project has no handoff yet.
2. If the user referenced a recent task, open the relevant log under DATA/logs/.
3. Check DATA/buffer/session-*.md for unconsumed buffers (a prior session that ended without a handoff) — distill or summarize them before proceeding.