heuristic

Context: this sub-skill is one lens of the broader

ui-craft

skill. If the

ui-craft

skill is also installed, read its SKILL.md first for Discovery + Anti-Slop + Craft Test, then apply the specific lens below.

Score the UI at

$ARGUMENTS

against Nielsen's 10 + 6 design laws. Load the

ui-craft

skill.

Step 1 — Load the methodology. Read

references/heuristics.md

for the full rubric, scoring definitions, design law details, and the required output format. Do NOT invent a new format or a new scale.

Step 2 — Walk Nielsen's 10 heuristics. Score each 1-5 per the rubric:

1 blocks users · 2 severe friction · 3 works but confusing · 4 works, minor polish · 5 best-in-class

For every heuristic, write a concrete finding — quote text, count elements, name the broken flow. Vague findings are rejected.

Step 3 — Audit the 6 design laws. PASS / FAIL each with a specific detail:

Fitts's Law — touch target sizing, CTA placement
Hick's Law — choice density, nav + select sizing
Doherty Threshold — perceived latency, optimistic UI
Cleveland-McGill — chart encoding choice
Miller's Law — nav depth, form section counts
Tesler's Law — where complexity lives

Step 4 — Persona walkthrough (if
--persona=
present). If the args include

--persona=<name>

, load

references/personas.md

and run the matching walkthrough checklist. Supported:

priya

jordan

adaeze

kwame

margo

all

. Output the walkthrough as a

| Checklist item | Pass/Fail | Finding | Impact |

table. Without the flag, skip this step.

Step 5 — Rank findings by impact tag. Impact order:

blocks-conversion > adds-friction > reduces-trust > minor-polish

. Include at most 5 findings in the ranked list; cut anything at

minor-polish

unless there are no higher-impact findings.

Step 6 — Compute the UsabilityScore. Roll the scorecard into a 0-100 number + grade per the UsabilityScore formula in

references/heuristics.md

heuristic_base = round(((mean(nielsen_scores) − 1) / 4) × 100)

, minus

5 × (failed design laws)

, clamped [0,100]. Same A/B/C/D/F bands as UICraftScore. Always label it

(judged)

— it is not deterministic and must never gate CI. If the args include

--json

, also emit the machine-readable block. If the user asks for the full picture, build the Extended quality report by fetching the deterministic UICraftScore (

node scripts/eval.mjs <path> --json

or the

score_ui

MCP tool) and placing both side by side — never average them.

Step 7 — Output. Use the exact scorecard format in

references/heuristics.md

```
## Heuristic Scorecard
```
table
```
## Design Law Audit
```
table
```
## Persona Walkthrough
```
table (only if
```
--persona=
```
was passed)
```
## Top findings (ranked by impact)
```
— numbered list, 3-5 items
```
## UsabilityScore
```
block — the 0-100 score + grade + component breakdown

Knob awareness: knob-agnostic. Usability is not a knob — a 2 is a 2 whether

CRAFT_LEVEL

is 3 or 9. Do not soften scores based on

CRAFT_LEVEL

Output contract:

This command produces a critique artifact, not code. No edits unless the user explicitly asks in a follow-up.
The scorecard is machine-parseable markdown. A PM can paste it into any issue tracker and file tickets row-by-row. Frame it that way in any preamble.
No "First Impressions" paragraph, no hedging, no praise padding. Tables + ranked list only.

Do NOT edit code. This is a scored critique.

Next step: Fix the findings, then

/finalize

— the scorecard is the input to a gated ship (rung 3).

heuristic

NPX Install

Tags

SKILL.md Content