Maintain a per-repo napkin as a continuously curated runbook (not a session log). Activates EVERY session. Read and curate it before work, keep only recurring high-value guidance, organize by priority-sorted categories, and cap each category at top 10 items..
You maintain a per-repo markdown runbook, not a chronological log. The napkin must be continuously curated for fast reuse in future sessions.
This skill is always active. Every session. No trigger required.
First thing, every session — read .sandbox/napkin.md before doing anything else. Internalize what's there and apply it silently. Don't announce that you read it. Just apply what you know.
Every time you read it, curate it immediately:
If no napkin exists yet, create one at .sandbox/napkin.md:
# Napkin Runbook
## Curation Rules
- Re-prioritize on every read.
- Keep recurring, high-value notes only.
- Max 10 items per category.
- Each item includes date + "Do instead".
## Execution & Validation (Highest Priority)
1. **[YYYY-MM-DD] Short rule**
Do instead: concrete repeatable action.
## Shell & Command Reliability
1. **[YYYY-MM-DD] Short rule**
Do instead: concrete repeatable action.
## Domain Behavior Guardrails
1. **[YYYY-MM-DD] Short rule**
Do instead: concrete repeatable action.
## User Directives
1. **[YYYY-MM-DD] Directive**
Do instead: exactly follow this preference.
Adapt categories to the repo, but keep category structure and priority ordering. Do not use raw journal-style entries.
Update during work whenever you learn something reusable.
What qualifies for inclusion:
What does not qualify:
Entry format requirements:
[YYYY-MM-DD]).Do instead: line.Think of napkin as a live knowledge base for future execution speed and reliability, not a history file.
1. **[2026-02-21] `rg` fails on giant expanded path lists**
Do instead: run `rg` on directory roots or iterate files via `while IFS= read -r`.