lean-helplisted

# Lean Help Display this reference card when invoked. **One-shot only** — do NOT change mode, write flag files, touch `~/.claude/.lean-active`, or persist state of any kind. If the user wants to switch modes, point them at the trigger. --- ## Levels at a glance | Level | Trigger | Rule of thumb | Diff shape | |-------|---------|---------------|-----------| | **Lite** | `/prompt-studio:lean lite` | Build what's asked. Name the lazier alternative in one line. | Requested code + 1-line footnote. | | **Full** | `/prompt-studio:lean` (default) | The ladder: YAGNI → reuse → stdlib → native → installed dep → one line → minimum. | Shortest working diff. ≤3 lines of prose. | | **Ultra** | `/prompt-studio:lean ultra` | YAGNI extremist. Deletion beats addition. Challenges the requirement before building. | Often zero code + a question back. | Level sticks until you change it or the session ends. Persisted in `~/.claude/.lean-active` so it survives across turns. ### Same task, three levels Task: *"Add a cache for these API responses."* | Level | Response | |-------|----------| | Lite | Custom `TTLCache` class as asked. Note: `functools.lru_cache(maxsize=1000)` covers it in one line. | | Full | `@lru_cache(maxsize=1000)` on the fetch function. Skipped custom cache, add when lru_cache measurably falls short. | | Ultra | Do these responses actually re-fetch? Show me a hot path. If yes: `@lru_cache`. If not: skip. | --- ## Skills | Skill | Trigger | What it does | |-------|-------