── ── Mental model
Checklist
A checklist is a short written list of must-not-skip steps for a complex repeated operation. It externalizes working memory — which fails under load, ego, time pressure, and fatigue — so attention stays on the situation rather than step recall. Boeing 1935 → Pronovost ICU 2001 → WHO Surgical 2008: each produced 36-47% reductions in major adverse events at near-zero…
How it works
Step 1 — Identify the operation: operation name, frequency, stakes of errors, current failure modes, near-miss history.
Step 2 — List 15-25 candidate items: steps that have been skipped, steps that prevent major errors, coordination steps, bias-catching steps, reversibility checkpoints.
Step 3 — Cut to 6-10: keep only items that are critical, easily missed by skilled operators, and verifiable (yes/no signal). Longer lists get truncated in use.
When to use it
- user says 'let's make sure we don't skip anything', 'we need a pre-flight', 'build me a checklist for X', 'we keep missing steps in our deployment / close / launch', 'Gawande / Pronovost / checklist manifesto'
When not to use it
the task is simple and one-off with no recurrence; the user is asking for a to-do list or project plan (not a must-not-skip operational gate).
Worked example
B-17 1935 + Pronovost ICU + WHO Surgical
The Boeing B-17 incident of October 30, 1935, is the canonical aviation case. The B-17 prototype was being demonstrated to the U.S. Army Air Corps at Wright Field. The crew included Major Ployer Hill, an experienced test pilot. The aircraft took off and immediately began to climb steeply, stalled, and crashed. Two of five aboard died, including Hill.
Install this skill (free, MIT)
npx skills add deciqAI/knowledge-skills