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.
/plugin marketplace add plannotator/effective-htmlnpx agentmods add plugins/plannotator/effective-html/marketplacegit clone --depth 1 https://github.com/plannotator/effective-htmlGrade A, and why
effective-html 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 yesterday.
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": "github",
"repo": "plannotator/effective-html"
},
"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"
}
]
}
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.
- yesterday First seen · 23 lines scan A 0d9354241d0f
effective-html is a plugin published in the GitHub repository plannotator/effective-html (2,735 stars, last pushed 28d ago), 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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