Onmark Video

What it does

When your agent uses it

• Onmark film.html files
• Screenplay timing
• Semantic video/audio/caption elements
• CSS/Canvas/WebGL presentation

Example prompts

• “/onmark-video”

Workflow steps

7 steps, taken from the first numbered list in SKILL.md.

1. 1onmark check film.html --json after every structural or timing edit.
2. 2onmark inspect film.html --json when reasoning about frames, partitions,
3. 3onmark snapshot film.html --frame 42 --json to inspect an exact production
4. 4onmark review film.html --json for a static film-wide contact sheet backed
5. 5onmark render film.html --output draft.mp4 after selected frames are sound.
6. 6Re-run the same command after edits; Onmark reuses only verified unchanged
7. 7onmark benchmark film.html --runs 3 --json only for measured performance

What it can do on your machine

Read from SKILL.md and the folder at commit ae455ab. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are html and bash).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Onmark Video loads about 1.2k tokens when it runs. Until then it costs about 94 tokens; SKILL.md has 504 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~94

When it runs · the whole SKILL.md, loaded when a task matches

~1.2k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from zihanyang-dev/onmark at commit ae455ab, republished under its MIT licence (© zihanyang-dev). 504 words, ~1,158 tokens.

name

onmark-video

description

Create, edit, validate, inspect, snapshot, review, benchmark, or render deterministic Onmark videos from one HTML screenplay. Use for Onmark film.html files, screenplay timing, semantic video/audio/caption elements, CSS/Canvas/WebGL presentation, seekable frame motion, CLI diagnostics, exact visual feedback, incremental rendering, or delivery and ProRes exports.

<style>
  .headline { color: white; font: 700 8vw/1 sans-serif; }
</style>

<om-film>
  <om-scene>
    <om-shot duration="3s">
      <om-title class="headline">Hello, motion.</om-title>
    </om-shot>
  </om-scene>
</om-film>

<script type="module" data-om-motion>
  import { frameMotion, interpolate } from "onmark/authoring";

  export const motion = frameMotion({
    title({ element, progress }) {
      element.style.opacity = String(interpolate(progress, [0, 0.2], [0, 1]));
    },
  });
</script>

onmark render film.html --output release.mp4
onmark render film.html --output edit.mov

© zihanyang-dev, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 1 other file in skills/onmark-video of zihanyang-dev/onmark.

• SKILL.md
• agents/openai.yaml

Open the folder on GitHubat commit ae455ab