Mono-Color Skill: One-Ink and Two-Ink Editorial Print Image Generation

What Mono-Color Skill Does and Who It Is For

Mono-color-skill is a Claude Code skill defined in a SKILL.md file that instructs Claude to generate editorial images using the constraints of one-color or two-color print production. The README describes its core function: turn a theme, sentence, object, or supplied photograph into an original editorial image.

The default mode is controlled two-ink, with one dominant plate and one narrowly assigned accent plate. An explicit one-ink request produces a pure single-color result. The skill is intended for designers, content creators, and brand teams who produce posters, zines, event materials, packaging, Xiaohongshu covers, WeChat article headers, podcast covers, and editorial illustrations. Using one or two inks reduces print production costs while maintaining a distinctive visual style.

The Ink System: Palettes, Substrates, and Two-Ink Recipes

The skill defines eight single-ink options: Cobalt (#2148B8), Royal Blue (#2058D4), Botanical Green (#008A4B), Mint Green (#5EB783), Terracotta Orange (#C65F38), Signal Red (#C83232), Aubergine (#63365F), and Charcoal (#30343A).

For two-ink work, nine named recipes are provided, including Powder Blue + Signal Red (#9EB8D3 + #C83232), Cobalt + Terracotta (#2148B8 + #C65F38), and Botanical Green + Oxblood (#008A4B + #8F3434). In two-ink compositions, the dominant plate carries 70-85% of the printed area. The accent plate carries 15-30% and must have a specific job: dates, annotations, selected objects, or overprint intersections. The substrate is not counted as a third color, and the darker tone created where two plates overlap is not considered a third ink.

Three substrate options are available. Neutral White (#FAFAF7) is used for crisp cultural, social, event, and image-led work. Cool Gray (#E9E9E5) is used for architecture, technology, charcoal-led systems, and restrained branding. Pale Beige (#F5F1E8) is used for tactile, travel, food, intimate, archival, or explicitly nostalgic subjects. The README states that limited inks and halftone do not automatically imply vintage styling.

The Five-Step Generation Workflow

The README documents the generation process in a fixed sequence:

1  Read the input       →  identify subject, intent, words, and image role
2  Choose the layout    →  image, specimen, declaration, object field, overprint, journal, or cover
3  Assign the plates    →  default to two assigned roles; switch to one plate when explicitly requested
4  Compose the page     →  preserve 25%–55% silence and add one deliberate disruption
5  Generate and inspect →  check ink count, identity, hierarchy, texture, and originality

The layout step selects from seven named layout types. Step 3 makes the ink assignment explicit before any generation happens, which is what prevents accidental use of three or more colors. Step 4 enforces the empty-space rule: between 25% and 55% of the canvas must remain as visible paper. Step 5 includes a final check that verifies the output has not drifted away from the ink constraint or introduced a generic composition.

Visual Rules and Typographic Roles

The README lists numbered visual rules that govern every output. No more than two printing inks are allowed. Paper must remain visible: the result should read as a printed page, not a digitally tinted monochrome wash. Photographs are rendered as halftone dots, risograph grain, cyanotype exposure effects, or photocopy breakup, not as clean full-color images. Empty paper occupies 25-55% of the canvas and controls pacing.

Typography follows a two-voice system: one content-responsive display skeleton and one utility voice. The skill supports literary serif, cultural grotesk, condensed civic, programmatic, rotated, handwritten, and word-as-object roles. Handwriting is listed as a short optional interjection rather than a primary voice, which prevents the output from drifting toward a casual hand-lettered style when the subject does not call for it.

The README also describes image treatment modes: pure one-ink, chromatic plus black, complementary duotone, and overprint duotone. The output from the skill includes the generated raster image, an exact production prompt, and a short recipe summarizing the ink and layout choices made.

Repository Structure and What Each Directory Contains

The top-level directory includes SKILL.md, which defines the actual Claude skill. The design-system/ directory holds the visual system specifications. The evals/ directory contains evaluation files, which suggest the repository includes tests for validating that the skill produces outputs conforming to the visual rules. The examples/ directory holds 12 reference images (reference-01.png through reference-12.jpg) that informed the visual system, plus 12 generated output examples showing the skill's range across cycling, field study, packaging, and photography subjects.

A REFERENCES.md file provides the complete index, research notes, attribution status, and a correction link for the 12 reference images, which remain the property of their respective creators. A CHANGELOG.md tracks changes to the skill. The README states that the twelve-image research set informed the visual system rather than serving as templates to reproduce.

The repository has no GitHub releases. Version history is available only through git commit history.

Limitations: What the Skill Enforces and What It Cannot Do

The skill is built around constraints that are design features but also limits for certain use cases. The two-ink maximum means any request for a three-color palette, a full-color photograph treatment, or a gradient-rich composition is outside its scope. The README is explicit that paper must stay visible, which rules out dark-background poster styles where the entire surface is inked.

The README was truncated at the visual rules section, so the full list of visual rules documented in the repository is not available here. The README does not document how SKILL.md is installed or invoked within a Claude Code project. A developer who needs to configure or extend the skill must read SKILL.md directly.

The use cases listed are all relatively small-format editorial items: social media covers, packaging stickers, zine interiors, and event posters. Large-scale print production that requires print-ready CMYK files or vector output is outside what the skill generates, since its output is a raster image.

Comparison with Midjourney: Constrained System versus Open-Ended Generation

Midjourney is a widely used text-to-image generation service that can produce editorial-looking images given a descriptive prompt. A skilled Midjourney user can approximate a risograph or duotone aesthetic by including those words in a prompt. The key difference is that the result is not enforced: Midjourney may introduce a third color, ignore the empty-space rule, or apply an inconsistent typographic treatment from prompt to prompt.

Mono-color-skill treats ink count, substrate choice, plate assignment, and empty-space percentage as constraints applied at generation time and checked afterward. It produces not just an image but also an exact production prompt and a short recipe, making it possible to replicate or vary the result systematically. For a designer who wants consistent ink-count discipline across a campaign or publication, the built-in check is useful. For a designer who wants maximum expressive flexibility, Midjourney's open-ended approach is the better fit.

The skill is MIT licensed, while Midjourney is a commercial service with its own usage terms.

Editorial conclusion

Designers and content creators who want consistent editorial print aesthetics from AI-generated images will find the ink-count rules, substrate selection, and typographic role system useful for maintaining a coherent visual identity across posters, social media covers, and packaging. Those expecting a general-purpose image generator that handles photorealistic output or full-color imagery will find this the wrong fit: it enforces a one-ink or two-ink constraint throughout. The last push was on 2026-09-02. To verify whether the skill covers your specific use case, read SKILL.md before integrating it into a project.

Frequently asked questions

Official sources

1. Issues
2. License: MIT
3. README
4. yanliudesign/mono-color-skill on GitHub