Effective HTML is a collection of agent skills for creating self-contained HTML artifacts such as wireframes, interactive prototypes, plans, diagrams, reports, and tools. It helps coding agents turn reference material and prompts into visual, usable HTML deliverables, and the catalogue entries are its installable skills and plugins.
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.
git clone --depth 1 https://github.com/plannotator/effective-htmlWrote 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/plugins/plannotator/effective-html/marketplace)<a href="https://agentmods.dev/plugins/plannotator/effective-html/marketplace"><img src="https://agentmods.dev/badge/plugins/plannotator/effective-html/marketplace/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/plugins/plannotator/effective-html/marketplace"><img src="https://agentmods.dev/badge/plugins/plannotator/effective-html/marketplace.svg" alt="Reviewed on agentmods" width="80" height="20"></a>Grade A, and why
effective-html marketplace 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.
What it actually says
{
"name": "effective-html",
"owner": {
"name": "plannotator"
},
"description": "Creative direction and focused skills for self-contained HTML artifacts, wireframes, interactive prototypes, plans, and diagrams.",
"plugins": [
{
"name": "plannotator-effective-html",
"source": {
"source": "url",
"url": "https://github.com/plannotator/effective-html.git"
},
"description": "Give standalone HTML artifacts a subject-specific visual direction, then create wireframes, styled mockups, interactive prototypes, plans, diagrams, and general artifacts.",
"homepage": "https://github.com/plannotator/effective-html",
"repository": "https://github.com/plannotator/effective-html",
"license": "MIT",
"keywords": ["html", "design", "creative-direction", "wireframe", "prototype", "prototyping", "diagram", "plan", "html-artifacts", "agent-skills", "claude-code", "codex"],
"category": "productivity"
}
]
}
The plugins it lists here
This marketplace lists 1 plugin kept in the same repository. Each has its own page, its own measurements and its own install command.
What ships with it
1 file beside marketplace.json in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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 Changed f0825e1392b8
- 1mo ago First seen · 23 lines scan A 0d9354241d0f
effective-html marketplace is a plugin published in the GitHub repository plannotator/effective-html (3,669 stars, last pushed yesterday), licensed MIT. Its token cost is not measured: this kind of file is read by the harness, not the model. 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 2026-08-30.
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liquid-glass
Apple-style liquid glass: frosted, refracting surfaces for web UI, with the rules that keep them from reading as gray boxes.
glyphs-reference
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architect-toolkit
Essential architect tools: katas, interview prep, review facilitation, mentoring, anti-patterns, audits, and pattern catalogs.