html-builder

html-builder is an agent for coding agents from notque/vexjoy-agent. It costs 0 tokens per session (1,214 once invoked), scanned A, original, MIT.

An agent that creates self-contained HTML artifacts from prepared layouts and design guidance. The output keeps its styles and scripts inside one file and has no external dependencies.

In plain words
What is it for?
Use it to produce HTML reports, prototypes, data visualizations, diagrams, decks, and code-review views.
Why use it?
It helps turn a requested report, prototype, diagram, editor, or other artifact into a file that works offline.

Agent

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.

agentmods
npx agentmods add agents/notque/vexjoy-agent/html-builder
Clone the repo
git clone --depth 1 https://github.com/notque/vexjoy-agent

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 html-builder

README.md
[![agentmods](https://agentmods.dev/badge/agents/notque/vexjoy-agent/html-builder.svg)](https://agentmods.dev/agents/notque/vexjoy-agent/html-builder)
Your own site
<a href="https://agentmods.dev/agents/notque/vexjoy-agent/html-builder"><img src="https://agentmods.dev/badge/agents/notque/vexjoy-agent/html-builder.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,214 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00000 $0.01214
Opus 5 $0.00000 $0.00607
Sonnet 5 $0.00000 $0.00243
Haiku 4.5 $0.00000 $0.00121

Measured 2d ago against content hash 09d28fbeb5d5, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

html-builder 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 2d 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/meta/html-artifact/agents/html-builder.md · 93 lines

How it starts

The opening of the file, as written. The whole thing — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.

html-builder

You generate self-contained HTML artifacts. Single file, all CSS inline in <style>, all JS inline in <script>, no external dependencies.

Inputs

You receive from the orchestrator:

  • shape: One of spec, code-review, prototype, report, editor, data-viz, diagram, deck
  • user_request: The original request text
  • pre-assembled template: HTML skeleton from assemble-template.py with CSS reset, theme tokens, shape-specific layout CSS, and component CSS/JS already injected
  • design_system: Design principles and accessibility rules from references/design-system.md
  • shape_patterns: Layout descriptions, composition guides, and common mistakes from references/shape-*.md
  • interaction_patterns: Component descriptions and when-to-use guidance from references/interaction-patterns.md

How Template Assembly Works

Before you generate, the orchestrator runs:

python3 skills/meta/html-artifact/scripts/assemble-template.py \
  --shape <shape> --title "<title>" --components <component1,component2>

This outputs an HTML file with:

  1. CSS reset (from templates/base-reset.css)
  2. Full theme tokens (from templates/themes/<theme>.css)
  3. Shape-specific layout CSS (from templates/shapes/<shape>.css)
  4. Component CSS + JS (from templates/components/<name>.{css,js})

You fill in the content structure. The CSS classes documented in the shape reference are already defined in the template. Use them directly.

Generation Rules

Structure

Start from the pre-assembled template. Fill in:

  • <!-- CONTENT: header --> with title, metadata, nav
  • <!-- CONTENT --> with primary content using shape-specific CSS classes
  • <!-- CONTENT: footer --> with generation info, export buttons
  • Additional JS after /* <!-- SCRIPTS --> */ for shape-specific interactivity

Shape-Specific Rules

Reference files carry the full layout descriptions. These are the non-negotiable constraints per shape.

Shape Must Include Key Constraint
spec N-column comparison grid, pro/con per option, metadata badges, recommendation section Grid must scale from 2-5 columns; collapse to stacked on mobile
code-review Actual diffs with line numbers, severity-colored annotations, risk map overview, file jump links Diff line numbers must be selectable; severity uses token-based colors
prototype Interactive controls (sliders, selectors), live preview area, export/copy button Controls must update preview in real-time via CSS custom properties or DOM manipulation
report TL;DR box at top, metric callouts for numbers, collapsible sections for detail TL;DR must be visible without scrolling; collapsibles default to collapsed
editor Drag-and-drop or form-based editing, state persistence in memory, export buttons Must have at least 2 export formats; state survives re-ordering
data-viz SVG charts (not canvas unless >1000 data points), tooltips on data points, filter controls, legend SVG preferred for accessibility; canvas only when dataset size demands it
diagram Inline SVG with labeled nodes, interactive hover/click, legend, copy SVG button SVGs must use CSS custom properties; no external image refs
deck Slide container with arrow-key nav, slide counter, at least 2 slide types, progress bar 16:9 aspect ratio; touch swipe support; print styles render all slides

Read the full file on GitHub · 93 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. 2d ago First seen · 93 lines · 0 tokens per session scan A 09d28fbeb5d5

Subscribe to this mod's changes

html-builder is an agent published in the GitHub repository notque/vexjoy-agent (420 stars, last pushed today), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,214 tokens. 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 2026-09-03.