apply-color-theory-principles

apply-color-theory-principles is a skill for Claude Code from jeffreytse/grimoire-core. It costs 32 tokens per session (1,094 once invoked), scanned A, original, MIT.

A guide to choosing and combining colours in painting, design, and illustration. It covers harmony, contrast, mood, and the visual order created by different colours.

In plain words
What is it for?
Use it to build colour palettes, improve contrast, set a mood, and draw attention to important parts of an image or design.
Why use it?
It gives a structured way to make colour choices when colours look different depending on their surroundings or clash when combined.

Skill for Claude Code

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

Part of the grimoire-art plugin — 18 skills shipped together

Good fit Use it to build colour palettes, improve contrast, set a mood, and draw attention to important parts of an image or design.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/jeffreytse/grimoire-core/apply-color-theory-principles
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 jeffreytse/grimoire-core --skill apply-color-theory-principles
Clone the repo
git clone --depth 1 https://github.com/jeffreytse/grimoire-core

Made for: Claude Code.

Or install grimoire-art, the plugin that ships this one along with the rest of its 18 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 apply-color-theory-principles

README.md
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Your own site
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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.

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Your own site · 80×15
<a href="https://agentmods.dev/skills/jeffreytse/grimoire-core/apply-color-theory-principles"><img src="https://agentmods.dev/badge/skills/jeffreytse/grimoire-core/apply-color-theory-principles.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 32 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,094 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 $0.00032 $0.01094
Opus 5 $0.00016 $0.00547
Sonnet 5 $0.00006 $0.00219
Haiku 4.5 $0.00003 $0.00109

Measured 11d ago against content hash c67dc2ac3732, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

apply-color-theory-principles 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 11d 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.

skills/art/color-theory/skills/apply-color-theory-principles/SKILL.md · 53 lines

How it starts

The opening of the file, as written. The whole thing — 53 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Apply Color Theory Principles

Make deliberate, structured color decisions using the scientific and perceptual frameworks developed by Itten, Albers, and Munsell.

Why This Is Best Practice

Adopted by: Bauhaus curriculum (Itten's foundational course, 1919–1923); RISD, Yale School of Art (Albers' Interaction of Color program), and every accredited fine art and design school worldwide; Munsell system adopted by US Federal standards (USDA soil color charts, architectural specification systems) Impact: Designers trained in formal color theory report 40% fewer client revision cycles on palette decisions; Albers' simultaneous contrast principles are the direct basis for web accessibility contrast ratio standards (WCAG 2.1) used in billions of digital interfaces Why best: Color perception is relative and context-dependent — colors that appear harmonious in isolation clash in context, and vice versa; systematic color theory provides predictive tools that survive context changes and scale across media

Sources: Johannes Itten "The Art of Color" (1961); Josef Albers "Interaction of Color" (1963); Albert Munsell "A Color Notation" (1905)

Steps

  1. Identify the three color dimensions — every color has hue (the name: red, blue, etc.), value (lightness/darkness on a scale of 1–10), and saturation/chroma (intensity from gray to pure color); analyze any color problem by separating these three axes.
  2. Choose a harmonic relationship — select from Itten's seven color contrasts as the organizing principle: complementary (opposite hues), analogous (adjacent hues), triadic, split-complementary, tetradic, warm/cool contrast, or simultaneous contrast.
  3. Establish a value structure first — convert the composition to grayscale mentally or literally; if the value structure does not read clearly in grayscale, color will not rescue it.
  4. Apply the 60-30-10 ratio — assign approximately 60% of the composition to a dominant hue, 30% to a secondary, 10% to an accent; this prevents equal competition between colors.
  5. Use simultaneous contrast deliberately — any color shifts in appearance depending on its neighbor; a gray looks warm next to cool blue and cool next to warm orange; use this to push colors without changing them.
  6. Control saturation to establish hierarchy — the most saturated color in a composition draws the eye first; reserve maximum saturation for the focal point and desaturate surrounding areas proportionally.
  7. Adjust temperature relationships — warm colors advance visually, cool colors recede; use warm shadows or cool lights (or vice versa) to create atmospheric depth without altering value.
  8. Test in context — never evaluate a color in isolation; always view it surrounded by the colors it will sit next to in the final work.
  9. Check at reduced size — thumbnail the composition at 10% scale; if the color relationships still read as intended, the palette is robust; if they collapse, the contrasts are too subtle.
  10. Name and record successful palettes — document hue angle, saturation percentage, and value for each color to enable precise reproduction across media and tools.

Read the full file on GitHub · 53 lines

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. 11d ago First seen · 53 lines · 32 tokens per session scan A c67dc2ac3732

Subscribe to this mod's changes

apply-color-theory-principles is a skill published in the GitHub repository jeffreytse/grimoire-core (4 stars, last pushed 22d ago), licensed MIT. It adds 32 tokens to every session and 1,094 once invoked, about $0.0002 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.