Guide · Agent skill
How to use the Anti-Slop Human Accessibility Skill agent skill
Updated · written with AI from the project's own documentation and checked against our catalogue data
The antislop-human skill is an agent skill for the Anti-Slop rules set. It makes an AI coding agent check the basics of accessibility when it builds or edits a user interface: text and control contrast, keyboard operation, visible focus, and interactions that exclude people. This guide explains what the skill does, how to install it, how to trigger it, and where its limits are, so you can use it on your own front-end work.
Anti-Slop Human Accessibility Skillmiqdadbadjuber/anti-slop · MIT Download the skill Quick start
- 1Download and unzip. Download the skill ZIP from this page and unzip it so the folder is named antislop-human.
- 2Place the folder. Move it to ~/.claude/skills/ for all projects, or to the project's .claude/skills/ folder for one project. Alternatively, upload it in the Claude apps under Settings, then Capabilities, then Skills.
- 3Make a UI request. Ask the agent to build or edit a UI and mention contrast, keyboard or focus so the skill loads.
- 4Check color pairs. Have the agent run contrast-check.py with two hex colors, or apply the formula if Python is unavailable.
- 5Review the result. Read the ratio and pass or fail verdicts for normal and large text, and fix any failing pairs.
What does the antislop-human skill make the agent do?
When an agent builds or edits UI, the skill directs it to check whether text and controls have enough contrast against their backgrounds, whether every control works with a keyboard and shows a visible focus indicator, and whether interactions such as hover-only menus are avoided.
For color pairs the agent cannot judge by eye, the skill says to calculate the WCAG contrast ratio rather than guess. It can do this with the bundled contrast-check.py script or by applying the formula written in SKILL.md. The skill is meant to be used alongside a core antislop rules file (antislop.md).
- Contrast for normal text (4.5:1) and large text (3:1, 18px+)
- Non-text contrast of 3:1 for component boundaries and status indicators
- Keyboard reachability, Enter or Space activation and Escape to close dialogs
- Visible focus indicators and logical tab order
- Mobile details that exclude people, such as zooming and the on-screen keyboard
Install the skill from a ZIP file
Download the ZIP of the skill from this page and unzip it. The folder should be named antislop-human and contain SKILL.md, contrast-check.py, contrast-mcp.py and a references folder.
For a personal install that applies to all your projects, place the folder in ~/.claude/skills/. To limit it to one project, place it in that project's .claude/skills/ folder.
In the Claude apps you can instead upload the skill under Settings, then Capabilities, then Skills.
Trigger the skill with natural requests
You do not need a special command. Load the skill by asking for UI work that involves accessibility, for example asking the agent to check the contrast of a color palette or to make a new form work with a keyboard. The skill's description covers contrast, keyboard, focus, states and interaction affordances.
Name the files or colors you care about. The more specific the pairing, the more reliably the agent will run the checker instead of estimating.
- Check whether #777777 text on white passes WCAG AA for body copy.
- Review this component's focus styles and make sure every button is keyboard operable.
- Build a settings dropdown that opens with Enter and closes with Escape.
- Audit the hero section text over this background image for contrast.
Run the contrast checker
When Python 3 is available, the agent can run the checker from the skill folder. It takes two hex colors and prints the ratio and a verdict for normal and large text. Use python3 on macOS and Linux and python on Windows.
If the script is missing or Python is not available, the skill says the formula and reference table in SKILL.md are complete on their own, and the agent should not block on the script. Near a threshold, the skill says to trust the unrounded ratio, so a result of 4.498:1 fails 4.5:1 even though it displays as 4.50.
- Relative luminance is calculated per channel, then the ratio is (L1 + 0.05) / (L2 + 0.05).
- The maximum ratio is 21.0 (black on white).
- contrast-mcp.py is an optional tool for MCP-capable clients.
python3 "${CLAUDE_SKILL_DIR}/contrast-check.py" "#FFFFFF" "#777777"
# normal text: FAIL (4.48 < 4.5)
# large text: PASS (4.48 >= 3.0)Know what the skill does not cover
The skill covers a few patterns and a contrast checker. Its reference files may be incomplete compared with the full WCAG standard. It does not do screen reader testing or a complete WCAG review.
Treat the skill as a fast, scripted first pass. Projects that need certified compliance still require testing with real assistive technology and real users.
Safety notes: scripts and network
The skill runs scripts: contrast-check.py is a Python script, and the skill's allowed tools include Bash for python and python3 commands. It does not use the network. Read the script before running it if you want to confirm what it does.
- Requires Python 3 for contrast-check.py
- Uses no network access
- Licensed under MIT
What people use it for
- Checking a brand color palette for readable body text and visible button boundaries before a design review.
- Making an AI-generated form keyboard operable with visible focus indicators.
- Replacing a hover-only navigation menu with one that opens by keyboard too.
- Verifying white text over a hero image across its whole area, not one bright spot.
Frequently asked questions
How do I install the antislop-human skill?
Download the ZIP from this page and unzip it. Place the antislop-human folder in ~/.claude/skills/ for all projects or in a project's .claude/skills/ folder for one project. In the Claude apps you can also upload it under Settings, then Capabilities, then Skills.
What do I need to run the contrast checker?
Python 3 is needed to run contrast-check.py, and the script is run with python3 on macOS and Linux or python on Windows. The skill says it can fall back to the formula in SKILL.md without Python. An MCP-capable client is optional if you want to use contrast-mcp.py as a tool.
Is the antislop-human skill free to use?
The skill is released under the MIT licence, as stated on this page. Check the licence file included with the skill for the full terms.
Does this skill replace a full accessibility audit?
No. It covers a few patterns and a contrast checker. It does not do screen reader testing or a complete WCAG review, and its reference files may be incomplete relative to the full standard.
Does the skill need internet access?
No, the skill does not use the network. It does run scripts, so it is worth reading contrast-check.py before you run it.
How is this different from just asking the AI to check contrast?
The skill tells the agent not to assert that a color pair passes without a computation. For pairs it cannot judge by eye, it calculates the WCAG ratio with the script or the formula instead of relying on the model's estimate.
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Our verdict
Use antislop-human if you are a front-end developer or designer who wants an AI agent to catch common contrast and keyboard problems with a scripted check instead of guessing. Pick a dedicated audit tool, and test with real assistive technology and users, if you need a complete WCAG review or certified compliance.
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