Glyph

Generate terminal demo GIFs from natural language descriptions. No real commands executed — everything is synthetic.

A Claude Code plugin that creates polished asciicast recordings with realistic typing, configurable themes, and built-in PII auditing.

Install

claude plugin marketplace add heurema/emporium
claude plugin install glyph@emporium

Commands

Command	What it does
/glyph "description"	Generate a demo GIF from a natural language description
/glyph	Interactive mode — asks what to demo
/glyph themes	List available themes
/glyph preview <path>	Render an existing scene JSON to GIF

How It Works

description → scene JSON → asciicast v2 → PII audit → .cast → agg → .gif

1. Scene generation: Claude creates a scene JSON from your description — shell commands, app interactions, comments, pauses
2. Rendering: Converts beats to asciicast v2 events with realistic typing timing (seeded RNG for reproducibility)
3. PII audit: Scans output for home paths, emails, API keys, secrets — blocks if found
4. GIF conversion: Pipes .cast through agg to produce the final GIF

Scene Format

{
  "version": "1.0",
  "config": {
    "cols": 100, "rows": 30,
    "shell_prompt": "$ ",
    "theme": "default",
    "title": "My Demo",
    "seed": 42
  },
  "beats": [
    {"type": "shell", "command": "cargo build", "output": ["Compiling myapp v0.1.0"], "pause_after": 1.0},
    {"type": "comment", "text": "# Build complete"},
    {"type": "pause", "duration": 2.0},
    {"type": "clear"}
  ]
}

Beat types: shell, app, comment, clear, pause.

Limits: max 50 beats, max 120s total duration.

Themes

Two built-in themes:

Theme	Description
default	Monokai colors, standard terminal look
amber	Retro amber-on-black CRT style

Custom themes: create a JSON file with prompt_color, output_color, comment_color, highlight_color, agg_theme, agg_font_size and pass it via --theme /path/to/theme.json.

Requirements

• Python 3.10+
• agg — for GIF output (brew install agg or cargo install agg)
• Claude Code

Without agg, the pipeline produces .cast files (viewable with asciinema play).

Privacy

• No real shell commands are executed
• PII audit blocks output containing home paths, emails, API keys, or secrets
• All data stays local

License

MIT