a2tl-video

A tool for creating animated explainers that play in a web browser. You describe the animation in a small .vdsl file, and it produces one self-contained HTML player instead of a video file.

In plain words
What is it for?
Use it to illustrate concepts, features, and processes in documentation, courses, landing pages, or presentations.
Why use it?
It avoids video encoding and external assets when an embeddable browser animation is enough. The result can be opened directly or placed in a webpage.

Skill for Claude CodeCodex

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 skills/anfaia/skillnet/skill
Any agent
npx skills add ANFAIA/SkillNet --skill skill
Clone the repo
git clone --depth 1 https://github.com/ANFAIA/SkillNet

Made for: Claude Code, Codex.

Per session 84 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,233 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 $0.00084 $0.02233
Opus 5 $0.00042 $0.01117
Sonnet 5 $0.00017 $0.00447
Haiku 4.5 $0.00008 $0.00223

Measured 2d ago against content hash 8c8e19845bff, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

a2tl-video 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.

packages/a2tl-video/skill/SKILL.md · 183 lines

How it starts

The opening of the file, as written. The whole thing — 183 lines — stays where its author put it; the contents beside it link to each section on GitHub.

A2TL-Video (web player)

Use this skill to turn content into an animated explainer. You write a small .vdsl file (a compact, ~30-100 line spec) and A2TL-Video renders it to a single, self-contained HTML file that plays instantly in any browser -- auto-fitting stage, play/pause, and a scrub bar, all inline with no build step and no external assets. There is no MP4 and no video-encoding step: the deliverable is the web player, which also embeds directly into a page.

A2TL-Video is part of the A2TL (Agent to Transformation Language) family alongside a2tl-web (for web pages).

When to use

  • User wants a video/animation about a concept, feature, or process
  • User wants to add an animated explainer to documentation, a course, or a landing page
  • User says "make a video about…", "animate this", "create an explainer for…"

How to use

  1. Read the content the user wants to visualize.
  2. Write a .vdsl file (see the format below).
  3. Produce the player, either way:
    • CLI: npx vdsl play <file>.vdsl -- writes <file>.html next to it. Open it to play; it embeds anywhere.
    • MCP tool: call render_player with { spec, theme?, output? }. It returns the self-contained HTML (and writes a .html when you pass output).
  4. Iterate on the spec and re-render. Do not try to produce an MP4 -- the product is the HTML web player.

Two more MCP tools help you stay accurate:

  • list_components — the components, viz types, reveals, transitions, positions, accents, fonts, and theme names this build supports.
  • list_icons — the exact icon names valid for icon "<name>".

Document structure

VDSL/1                      # required version header, must be the first line
theme dark-tech             # base theme (see Themes)
palette ink:"#0b1020" bg:"#f7f7f2"   # optional: inline colour overrides
font display:"Georgia" body:"Inter"  # optional: inline font overrides
canvas 1920x1080            # optional stage size (default 1920x1080)

scene "<title>" <duration>s <transition>
  <component> <args…> <timing>
  <component> <args…> <timing>

Read the full file on GitHub · 183 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 · 183 lines · 84 tokens per session scan A 8c8e19845bff

Subscribe to this mod's changes

a2tl-video is a skill published in the GitHub repository ANFAIA/SkillNet (11 stars, last pushed 3d ago), licensed Apache-2.0. It adds 84 tokens to every session and 2,233 once invoked, about $0.0004 per session on Opus 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 2026-08-30.