Describes an animation as a YAML timeline — canvas size and background, duration, loop, and layers (rect, circle, ellipse, line, text) whose keyframes set x, y, scale, rotate, opacity, size and fill at points in time with per-segment easing (linear, ease, ease-in, ease-out, ease-in-out, bounce, elastic) — and compiles it in the Worker to a self-contained HTML5 canvas player with play/pause, a scrubbable timeline and loop toggle, shown live in the script-enabled preview and downloadable as one HTML file. The same timeline is also exported as an SVG with SMIL animations that plays without any script. Everything runs locally.