Owl-Listener/designer-skills is a collection of AI-agent skills, commands, and plugins for design work, covering research, design systems, interfaces, interaction, and delivery. Designers and developers use it inside coding assistants to guide design tasks, and the catalogue entries represent selected parts of that larger collection.
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.
npx skills add Owl-Listener/designer-skills --skill law-of-similaritygit clone --depth 1 https://github.com/Owl-Listener/designer-skillsWrote 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.
[](https://agentmods.dev/skills/owl-listener/designer-skills/law-of-similarity)<a href="https://agentmods.dev/skills/owl-listener/designer-skills/law-of-similarity"><img src="https://agentmods.dev/badge/skills/owl-listener/designer-skills/law-of-similarity/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.
<a href="https://agentmods.dev/skills/owl-listener/designer-skills/law-of-similarity"><img src="https://agentmods.dev/badge/skills/owl-listener/designer-skills/law-of-similarity.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00047 | $0.00887 |
| Opus 5.5 | $0.00019 | $0.00355 |
| Sonnet 5.5 | $0.00009 | $0.00177 |
| Haiku 4.5 | $0.00005 | $0.00089 |
Grade A, and why
law-of-similarity 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 78 lines — stays where its author put it; the contents beside it link to each section on GitHub.
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.
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.
- 1mo ago First seen · 78 lines · 47 tokens per session scan A 06db562ff83e
law-of-similarity is a skill published in the GitHub repository Owl-Listener/designer-skills (3,137 stars, last pushed 1mo ago), licensed MIT. It adds 47 tokens to every session and 887 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-09-03.
Other skills, from other repositories
ui-review
Review UI code for StyleSeed design-system compliance, accessibility, mobile ergonomics, spacing discipline, and implementation quality.
design-craft
Design or substantially improve user-facing interfaces with a product-specific visual direction, content hierarchy, and rendered critique. Use for new screens, landing pages, redesigns, typography/layout work, or UI that feels generic or AI-generated. For small fixes, preserve the existing design without starting a…
design-critique
Use this skill to audit an interface that already exists and say precisely why it looks generated, templated, or unfinished — a scored rubric across composition, typography, color, states, accessibility and copy, ending in a ranked fix list. Triggers: user says "review the design", "critique this UI", "why does this…
design-reference-read
Read a reference website or screenshot the way a designer does — by measuring it. Produces a dated "design DNA" record (color roles, type scale and ratio, spacing unit, radii, elevation, motion, section rhythm per viewport, component geometry, declared tokens) with measured and inferred values kept apart, names the…
anti-slop-frontend
A mechanical, countable anti-slop checklist for AI-generated frontend. Catches the specific signatures an undirected model defaults to: AI-purple glows, Inter-everywhere, em-dashes, div-based fake screenshots, eyebrow-on-every-section, beige+brass "premium" palettes, generic Jane Doe / Acme data. Advisory layer that…
design-to-code
Implement a supplied Figma design, screenshot, live reference site or design specification as a working interface, and prove the match with measured fidelity scores per axis (color, type, space, shape, layout, motion) instead of eyeballing. Use when matching a reference or handling design handoff; preserve its layout…