heuristics

heuristics is a skill for Claude Code from fernando-bertholdo/4-successful-AI-life. It costs 119 tokens per session (4,381 once invoked), scanned A, original, MIT.

A usability review skill based on heuristic evaluation, a method for checking an interface against practical principles such as clear feedback, easy navigation, and low user effort.

In plain words
What is it for?
Use it for usability audits, UX reviews, confusing forms, navigation problems, heuristic evaluations, and cognitive walkthroughs.
Why use it?
It helps identify why users hesitate, get confused, or fail to complete tasks by examining the interface from a user’s point of view.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the ui-excellence plugin — 13 skills shipped together

Good fit Use it for usability audits, UX reviews, confusing forms, navigation problems, heuristic evaluations, and cognitive walkthroughs.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/fernando-bertholdo/4-successful-ai-life/heuristics
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add fernando-bertholdo/4-successful-AI-life --skill heuristics
Clone the repo
git clone --depth 1 https://github.com/fernando-bertholdo/4-successful-AI-life

Made for: Claude Code.

Or install ui-excellence, the plugin that ships this one along with the rest of its 13 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for heuristics

README.md
[![agentmods](https://agentmods.dev/badge/skills/fernando-bertholdo/4-successful-ai-life/heuristics/github.svg)](https://agentmods.dev/skills/fernando-bertholdo/4-successful-ai-life/heuristics)
Your own site
<a href="https://agentmods.dev/skills/fernando-bertholdo/4-successful-ai-life/heuristics"><img src="https://agentmods.dev/badge/skills/fernando-bertholdo/4-successful-ai-life/heuristics/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for heuristics

Your own site · 80×15
<a href="https://agentmods.dev/skills/fernando-bertholdo/4-successful-ai-life/heuristics"><img src="https://agentmods.dev/badge/skills/fernando-bertholdo/4-successful-ai-life/heuristics.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 119 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,381 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00119 $0.04381
Opus 5 $0.00060 $0.02191
Sonnet 5 $0.00024 $0.00876
Haiku 4.5 $0.00012 $0.00438

Measured 12d ago against content hash 8739a389400f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

heuristics scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

plugins/ui-excellence/skills/audit/heuristics/SKILL.md · 308 lines

How it starts

The opening of the file, as written. The whole thing — 308 lines — stays where its author put it; the contents beside it link to each section on GitHub.

UX Heuristics Framework

Practical usability principles for evaluating and improving user interfaces. Based on a fundamental truth: users don't read, they scan. They don't make optimal choices, they satisfice. They don't figure out how things work, they muddle through.

Core Principle

"Don't Make Me Think" - Every page should be self-evident. If something requires thinking, it's a usability problem.

The foundation: Users have limited patience and cognitive bandwidth. The best interfaces are invisible -- they let users accomplish goals without ever stopping to wonder "What do I click?" or "Where am I?" Every question mark that pops into a user's head adds to cognitive load and increases the chance they'll leave. Design for scanning, satisficing, and muddling through -- because that's what users actually do.

Scoring

Goal: 10/10. When reviewing or creating user interfaces, rate them 0-10 based on adherence to the principles below. A 10/10 means full alignment with all guidelines; lower scores indicate gaps to address. Always provide the current score and specific improvements needed to reach 10/10.

Krug's Three Laws of Usability

1. Don't Make Me Think

Core concept: Every question mark that pops into a user's head adds to their cognitive load and distracts from the task.

Why it works: Users are on a mission. They don't want to puzzle over labels, wonder what a link does, or decode clever marketing language. The less thinking required, the more likely they complete the task.

Key insights:

  • Clever names lose to clear names every time
  • Marketing-speak creates friction; plain language removes it
  • Unfamiliar categories and labels force users to stop and interpret
  • Links that could go anywhere create uncertainty
  • Buttons with ambiguous labels cause hesitation

Product applications:

Context Application Example
Navigation labels Use self-evident names "Get directions" not "Calculate route to destination"
CTAs Use action verbs users understand "Sign in" not "Access your account portal"
E-commerce Match user mental models "Add to cart" not "Proceed to purchase selection"
Form labels Describe what's needed plainly "Email address" not "Electronic correspondence identifier"
Error states Tell users what to do next "Check your email format" not "Validation error"

Read the full file on GitHub · 308 lines

Files

What ships with it

7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 12d ago First seen · 308 lines · 119 tokens per session scan A 8739a389400f

Subscribe to this mod's changes

heuristics is a skill published in the GitHub repository fernando-bertholdo/4-successful-AI-life (2 stars, last pushed yesterday), licensed MIT. It adds 119 tokens to every session and 4,381 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other skills, from other repositories

ux-spec

Generates UI/UX specifications with wireframes and design system. Creates UXSPEC.md and DESIGNSYSTEM.md from PRD and Architecture specs. Use when designing app interface and creating design system.

rshankras/claude-code-apple-skills · 41 tokens

liquid-glass

Implement Liquid Glass design using .glassEffect() API for iOS/macOS 26+. Covers SwiftUI, AppKit, UIKit, and WidgetKit. Use when creating modern glass-based UI effects.

rshankras/claude-code-apple-skills · 45 tokens

app-icon-generator

Generates an app icon for macOS or iOS — a fast CoreGraphics placeholder and/or flat layered source art to finish in Icon Composer (the Liquid Glass / iOS 26+ standard). Produces appearance variants (light/dark/tinted) and installs into the asset catalog. Use when the user wants to create, generate, iterate, or update…

rshankras/claude-code-apple-skills · 80 tokens

onboarding-generator

Generates value-moment-first onboarding flows for iOS/macOS apps — the default architecture races a new user to the first felt experience of the app's promised outcome, branching on whether they can experience it right now or need to plan for later. The classic paged welcome-carousel tour is an explicit fallback for…

rshankras/claude-code-apple-skills · 93 tokens

assistive-access

Assistive Access implementation for cognitive accessibility including simplified scenes, navigation icons, runtime detection, and design principles. Use when optimizing apps for Assistive Access mode.

rshankras/claude-code-apple-skills · 35 tokens

screenshot-planner

Plan compelling App Store screenshot sequences that showcase your app's value. Use when preparing App Store assets, improving screenshot conversion, or drafting screenshot captions for a launch or major update.

rshankras/claude-code-apple-skills · 40 tokens