Web Artifacts Builder
anthropics/skills
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Apply the Law of Similarity — shared colour, shape, or size signals that elements belong to one category.
Install Law Of Similarity
$ npx skills add Owl-Listener/designer-skills --skill law-of-similarity -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install Owl-Listener/designer-skills law-of-similarity --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/Owl-Listener/designer-skills.git skills-src && mkdir -p .claude/skills && cp -r skills-src/ui-design/skills/law-of-similarity .claude/skills/law-of-similarity && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "law-of-similarity" agent skill from https://github.com/Owl-Listener/designer-skills/tree/main/ui-design/skills/law-of-similarity into .claude/skills/law-of-similarity/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "law-of-similarity", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/Owl-Listener/designer-skills/tree/main/ui-design/skills/law-of-similarityType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add Owl-Listener/designer-skills --skill law-of-similarity -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install Owl-Listener/designer-skills law-of-similarity --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/Owl-Listener/designer-skills.git skills-src && mkdir -p .agents/skills && cp -r skills-src/ui-design/skills/law-of-similarity .agents/skills/law-of-similarity && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "law-of-similarity" agent skill from https://github.com/Owl-Listener/designer-skills/tree/main/ui-design/skills/law-of-similarity into .agents/skills/law-of-similarity/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "law-of-similarity", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add Owl-Listener/designer-skills --skill law-of-similarity -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install Owl-Listener/designer-skills law-of-similarity --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/Owl-Listener/designer-skills.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/ui-design/skills/law-of-similarity .cursor/skills/law-of-similarity && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "law-of-similarity" agent skill from https://github.com/Owl-Listener/designer-skills/tree/main/ui-design/skills/law-of-similarity into .cursor/skills/law-of-similarity/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "law-of-similarity", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/Owl-Listener/designer-skills.git --path ui-design/skills/law-of-similarity--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add Owl-Listener/designer-skills --skill law-of-similarity -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install Owl-Listener/designer-skills law-of-similarity --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/Owl-Listener/designer-skills.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/ui-design/skills/law-of-similarity .gemini/skills/law-of-similarity && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "law-of-similarity" agent skill from https://github.com/Owl-Listener/designer-skills/tree/main/ui-design/skills/law-of-similarity into .gemini/skills/law-of-similarity/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "law-of-similarity", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install Owl-Listener/designer-skills law-of-similarityInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add Owl-Listener/designer-skills --skill law-of-similarity -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/Owl-Listener/designer-skills.git skills-src && mkdir -p .github/skills && cp -r skills-src/ui-design/skills/law-of-similarity .github/skills/law-of-similarity && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "law-of-similarity" agent skill from https://github.com/Owl-Listener/designer-skills/tree/main/ui-design/skills/law-of-similarity into .github/skills/law-of-similarity/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "law-of-similarity", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add Owl-Listener/designer-skills --skill law-of-similarity -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install Owl-Listener/designer-skills law-of-similarity --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/Owl-Listener/designer-skills.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/ui-design/skills/law-of-similarity .opencode/skills/law-of-similarity && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "law-of-similarity" agent skill from https://github.com/Owl-Listener/designer-skills/tree/main/ui-design/skills/law-of-similarity into .opencode/skills/law-of-similarity/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "law-of-similarity", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
law-of-similarity- GitHub stars
- 2.9k
- Token cost
- ~1.2k tokens
- SKILL.md length
- 615 words
- Files
- 1
- Skills in repo
- 107
- Repo updated
- First seen
- Licence
- MIT
At a glance
Apply the Law of Similarity — shared colour, shape, or size signals that elements belong to one category.
- Signalling relationships across distance
- SKILL.md covers What You Do, The Principle, Similarity vs. Proximity and Design Applications, plus 2 more sections
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Law Of Similarity is an agent skill from Owl-Listener/designer-skills. Apply the Law of Similarity — shared colour, shape, or size signals that elements belong to one category. Use when signalling relationships across distance. For grouping by position, use law-of-proximity.
Its SKILL.md is about 1.2k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
It sits in Frontend & Design. The repository describes itself as: Designer Skills Collection: agentic skills, commands, and plugins for design — from research to systems, UI, interaction, and delivery. The licence is MIT.
When your agent uses it
- Signalling relationships across distance
Example prompts
- “/law-of-similarity”
What it can do on your machine
Read from SKILL.md and the folder at commit 9a6930c. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md.
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Law Of Similarity loads about 1.2k tokens when it runs. Until then it costs about 56 tokens; SKILL.md has 615 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
The full file from Owl-Listener/designer-skills at commit 9a6930c, republished under its MIT licence (© Owl-Listener). 615 words, ~1,162 tokens.
Download SKILL.mdSave it as
.claude/skills/law-of-similarity/SKILL.md (or your agent's skills folder).- name
- law-of-similarity
- description
- Apply the Law of Similarity — shared colour, shape, or size signals that elements belong to one category. Use when signalling relationships across distance. For grouping by position, use `law-of-proximity`.
Law of Similarity
You are an expert in Gestalt visual perception and systematic visual language design.
What You Do
You apply the Law of Similarity to use shared visual attributes — shape, color, size, and style — to signal that elements belong to the same category or group, and to maintain that coding consistently so the signal stays meaningful.
The Principle
Elements that share visual characteristics are perceived as related, even when they are not spatially adjacent. The mind groups by likeness automatically and without instruction.
Similarity can be carried through:
- Color: same fill signals same category, role, or state
- Shape: icons all the same style (outline vs. filled vs. rounded) read as a set
- Size: elements of equal size read as peers; size difference signals hierarchy
- Style: same illustration weight, same type treatment, same corner radius, same stroke width
Similarity vs. Proximity
These are the two most fundamental Gestalt grouping principles. They interact and can conflict:
| Situation | What happens |
|---|---|
| Elements close together, same color | Both reinforce — strongest grouping signal |
| Elements far apart, same color | Similarity groups them despite the distance |
| Elements close together, different colors | Proximity and similarity compete; the color pulls them into different sub-groups |
| Elements close together, different styles | Proximity groups the set; style difference creates sub-groups within it |
When they conflict, similarity can override proximity: a red element embedded in a group of blue elements reads as distinct even if it is spatially adjacent. Use this deliberately to signal category boundaries.
Design Applications
Interactive state signaling
All interactive elements should share a visual property (color, underline treatment, cursor affordance) that non-interactive elements do not. This tells users what is actionable without requiring explicit instruction — the similarity set defines the interactive category.
Category and role coding
- Navigation items as a set: consistent type treatment across all items
- Destructive actions: a distinctive color used only within that category — similarity within the set signals "these all carry the same risk"
- Status indicators: consistent color-to-meaning mapping (green = success, amber = warning, red = error) applied uniformly
When any element deviates from an established similarity set without purpose, users read the deviation as meaningful — as if the deviant element belongs to a different category.
Show full SKILL.md (256 more words)Show less
Design systems and component coherence
Similarity is the mechanism that makes a design system feel like one thing rather than a collection of unrelated components:
- Same button shape across all button variants
- Same input height and border treatment across all form elements
- Same icon stroke weight and style across all icons
Unintended similarity breaks — two buttons with slightly different corner radii that are supposed to be the same type — read as categorical differences. Treat them as bugs.
Data visualisation
- Same color = same data series across all charts in a report
- Same mark shape = same variable across chart types
- Grouping by similarity (color, shape) before spatial proximity is standard in multi-series visualisations
Common Mistakes
- Breaking similarity unintentionally: slight visual inconsistencies in what should be a uniform set signal a difference the designer did not intend
- Overusing a single attribute: coding too many distinct categories with the same color makes the attribute meaningless as a signal
- Relying on color similarity alone: colorblind users cannot distinguish groups encoded only through hue — always use redundant coding
Best Practices
- Define a similarity vocabulary in design tokens: which visual attributes encode which relationship types
- Treat unintended visual differences as bugs — if two elements should read as the same type, they must look identical
- Use redundant coding (shape + color, not color alone) for critical category signals so the information survives colorblind viewing and monochrome rendering
- Test similarity groupings without color: do elements still read as related from shape and size alone?
- Review dense layouts for unintended sub-groupings created by similarity interacting with proximity
© Owl-Listener, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
Just SKILL.md in ui-design/skills/law-of-similarity of Owl-Listener/designer-skills.
Open the folder on GitHubat commit 9a6930c
Compare with similar skills
Law Of Similarity next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Law Of Similarity this skillOwl-Listener/designer-skills | 2.9k | — | ~1.2k | Automated safety check: Pass | MIT | |
| Web Artifacts Builderanthropics/skills | 180k | 40 repos | ~769 | Automated safety check: Pass | Apache-2.0 | |
| React Doctormakeplane/plane | 61k | 12 repos | ~657 | Automated safety check: Pass | AGPL-3.0 | |
| Impeccablebestofjs/bestofjs | 3.1k | 26 repos | ~2.6k | Automated safety check: Pass | MIT | |
| Figma Design System Builderwarpdotdev/warp | 65k | 2 repos | ~4.4k | Automated safety check: Pass | AGPL-3.0 | |
| Web Interface Guidelines Reviewervercel-labs/openreview | 1.7k | 97 repos | ~308 | Automated safety check: Pass | None |
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Related
Categories
Questions about Law Of Similarity
What does Law Of Similarity do?
Apply the Law of Similarity — shared colour, shape, or size signals that elements belong to one category. Law Of Similarity is an agent skill from Owl-Listener/designer-skills. Apply the Law of Similarity — shared colour, shape, or size signals that elements belong to one category.
When should I use Law Of Similarity?
Law Of Similarity fits situations like: signalling relationships across distance.
How do I install Law Of Similarity in Claude Code?
Run `npx skills add Owl-Listener/designer-skills --skill law-of-similarity -a claude-code`. Or copy the skill folder (ui-design/skills/law-of-similarity in Owl-Listener/designer-skills) into .claude/skills/law-of-similarity in your project. Claude Code loads it when a task matches its description.
How do I install Law Of Similarity in Codex?
Run `npx skills add Owl-Listener/designer-skills --skill law-of-similarity -a codex`. Or copy the skill folder (ui-design/skills/law-of-similarity in Owl-Listener/designer-skills) into .agents/skills/law-of-similarity in your project. Codex loads it when a task matches its description.
Can I use Law Of Similarity in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add Owl-Listener/designer-skills --skill law-of-similarity -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/law-of-similarity, .gemini/skills/law-of-similarity, .github/skills/law-of-similarity and .opencode/skills/law-of-similarity in your project.
What does Law Of Similarity need to run?
SKILL.md names no scripts, command-line tools or credentials: Law Of Similarity is instructions for the agent only.
Does Law Of Similarity access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Law Of Similarity safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Law Of Similarity use?
Law Of Similarity is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Law Of Similarity use?
About 1.2k tokens (SKILL.md is roughly 4.6k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Law Of Similarity?
Skills that share tags, products or a category with Law Of Similarity: Web Artifacts Builder (anthropics/skills, 180k stars), React Doctor (makeplane/plane, 61k stars), Impeccable (bestofjs/bestofjs, 3.1k stars) and Figma Design System Builder (warpdotdev/warp, 65k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Law Of Similarity?
Owl-Listener (a GitHub user) maintains it in Owl-Listener/designer-skills, which has 2,871 GitHub stars. The repository holds 107 skills in this directory. The repository was last updated on September 5, 2026.
Source: Owl-Listener/designer-skills on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.