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 vaneenige/monochrome-ui --skill monochromegit clone --depth 1 https://github.com/vaneenige/monochrome-uiWrote 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/vaneenige/monochrome-ui/monochrome)<a href="https://agentmods.dev/skills/vaneenige/monochrome-ui/monochrome"><img src="https://agentmods.dev/badge/skills/vaneenige/monochrome-ui/monochrome/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/vaneenige/monochrome-ui/monochrome"><img src="https://agentmods.dev/badge/skills/vaneenige/monochrome-ui/monochrome.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00097 | $0.02380 |
| Opus 5.5 | $0.00039 | $0.00952 |
| Sonnet 5.5 | $0.00019 | $0.00476 |
| Haiku 4.5 | $0.00010 | $0.00238 |
Grade A, and why
monochrome 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 8d 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 — 178 lines — stays where its author put it; the contents beside it link to each section on GitHub.
monochrome
monochrome makes correctly marked-up HTML interactive. Import it
once; every component on the page works, including markup added
later (framework renders, innerHTML, streamed or generated HTML).
There is no init call, no state object, and no event wiring. The
DOM is the state: the core reads and writes ARIA attributes.
Components: Accordion, Collapsible, Dialog, Menu, Menubar, Popover, Tabs, Tooltip. Optional: Router.
The spec for the installed version is in
node_modules/monochrome/spec/, one file per component plus
choosing, conventions, styling, and router;
spec/<topic>.md below means that folder. Without the package
installed, npx monochrome docs <topic> prints the same pages.
Hard rules
- Ids wire everything.
mct:<kind>:<id>is a trigger,mcc:<kind>:<id>its content,mcr:<kind>:<id>a root. Every id is unique on the page. - Link both ways. Trigger
aria-controlsnames the content id; contentaria-labelledbynames the trigger id (a dialog names its title). Accordion panels arerole="region"; collapsible content links back only as arole="region". Tooltip triggers usearia-describedby. One id per attribute. - Triggers are
<button type="button">. Only tooltip triggers may be any focusable element. - Never write JS to open, close, select, or toggle. No
showModal(), nopopovertarget, nouseStatefor open state, no handler that flipshiddenoraria-*. The core does it. Handlers for what an item does (onClickon a menu item) are fine. - State lives in ARIA. Author the initial values
(
aria-expanded="false"plushidden,aria-selected,aria-checked), then let the core own them. Disable witharia-disabled="true", neverdisabled(the parts'disabledprop rendersaria-disabledfor you). - monochrome ships no CSS; style with attribute selectors:
[aria-expanded="true"],[aria-selected="true"],[aria-checked="true"],[data-mc-highlighted],:popover-open,dialog[open]. Menus, popovers, and tooltips need the Required CSS from their spec's Styling section, copied as it is: it places them at their trigger from the variables and the[data-mc-y]/[data-mc-x]side the core writes. Don't write placement of your own. Pick a side and alignment withdata-mc-side(top,right,bottom,left) anddata-mc-align(start,center,end) on the content. - One import family.
import "monochrome"(or the CDN script) for plain pages; in apps, the component filesaddwrites (each imports its ownmonochrome/<component>module). Never both: listeners would register twice. When React or Vue only renders HTML on the server (a static site, no client bundle of the component files), their imports never reach the browser: load the core once from the script every page runs, and drop the core import (and"use client") from the component files (spec/conventions.md, Server rendering). - Deliberate behaviour is not a bug. Each spec ends with Design choices: tabs select on Enter, not on focus; arrows skip disabled items; tooltips have no delay and never show on touch; menus open on press. Don't add code to change them.
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.
- 8d ago First seen · 178 lines · 97 tokens per session scan A 610edc862d25
monochrome is a skill published in the GitHub repository vaneenige/monochrome-ui (133 stars, last pushed 8d ago), licensed MIT. It adds 97 tokens to every session and 2,380 once invoked, about $0.0004 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 2026-10-08.
Other skills, from other repositories
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cognitive-accessibility
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contrast-master
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modal-specialist
Dialogs, drawers, popovers and overlays: focus trap, return and dismissal.
design-doctrine
The house rules for ANY design or UI work - the verification protocol (run the gate, never claim a number), the absolute no-emoji rule, token by intent, one shared theme, the eight states, one thing leads, and output completeness. Load this FIRST whenever building, reviewing, or theming a screen, component, or token…
image-to-code
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