Remove all layers and timelines from the scene (fresh start). Use before generating a complete new animation from scratch.

Change canvas composition settings (size, duration, framerate, background color).

Add a new layer to the scene. Set a meaningful id (e.g. "bg_rect", "title_text") — you will use this id in add_keyframes track targets.

Update properties of an existing layer. Only provide fields you want to change.

Remove a layer from the scene.

Create an animation timeline. You MUST create a timeline before calling add_keyframes. Set a meaningful id (e.g. "intro", "loop_anim") — you will reference it in add_keyframes.

Add keyframes to animate a layer property. Auto-creates timeline + track if missing.

TRACK TARGET FORMAT: "layers.{layerId}.{property}"

AVAILABLE PROPERTIES: opacity → 0.0 - 1.0 transform.x → pixels (horizontal position) transform.y → pixels (vertical position) transform.scaleX → 1.0 = 100% transform.scaleY → 1.0 = 100% transform.rotationDeg → degrees style.fill.color → "#rrggbb" hex string (SNAP — does NOT interpolate) style.fill.opacity → 0.0 - 1.0 style.stroke.width → pixels style.cornerRadius → pixels text.fontSize → pixels text.letterSpacing → pixels effects.blur → 0 - 100

EXAMPLES: target: "layers.bg_circle.opacity" target: "layers.title_text.transform.y" target: "layers.logo.transform.scaleX"

List all layers in the scene (terse): id, type, name, visibility. Use to discover what exists before editing.

List uploaded media assets (image/video/audio) with their ids. Use to find a valid assetId before add_layer type=image/video/audio. AI cannot upload files.

Detailed dump of one layer (transform, opacity, size, style, type-specific data).

List a timeline's tracks and their keyframes (target, times, values).

Full ChronoScene JSON. Use sparingly (large) — prefer list_layers / describe_*.

Compute animated property values at a given time (ms). Optionally filter to one target path (e.g. "layers.ball.transform.y"). Use to VERIFY an animation.

Create a state machine that switches between timelines based on events/guards. Create the per-state timelines FIRST, then this, then add_sm_state for each state. Use for interactive / multi-state scenarios (hover→active, idle→walk→run, 4 seasons…).

Add a state to a state machine. Each state plays one timeline while active. The first state added becomes the initial state automatically.

Connect two states with a transition. Fires on event, when guard holds, or both. Use from="*" for a transition that applies from any state.

Set which state a state machine starts in.

Add a particle emitter. Pick a preset by friendly name — confetti, sparkle, magic, smoke, fire, snow, rain, rocket — then optionally override count / durationMs / loop / position. Use for "confetti", "fireworks", "falling snow", etc.

Add a scene parameter — a named runtime value (number/boolean/color/string) that triggers, bindings, wires, and state-machine guards can read and write.

Add an event→action rule. When eventType fires (optionally on a layer/timeline), run one action (play/pause/seek a timeline, setParam, emitEvent…). Add an optional condition (condPath/condOp/condValue) to gate it. For click events, the layer must be tappable (set_interactive); for drag events, draggable.

Add a linear binding that remaps a source (parameter or layer property) onto a target (layer property / timeline progress / parameter) via inputMin→outputMin … inputMax→outputMax.

Add an expression-driven wire. The source value is bound as source (alias s) in a whitelist expression — map/clamp/lerp/min/max/abs/round/floor/ceil/sin/cos/tan/sqrt/pow/smoothstep — e.g. "map(source,0,1,0,360)". Source/target are scene params (propertyPath = param id, no layerId) or layer properties (layerId + dot-path).

Make a layer interactive: tappable (fires click triggers) and/or draggable (fires drag events). Drag can follow the cursor, drive a parameter (setsParameter), or scrub a timeline (scrubsTimeline).

Duplicate a layer. mode="copy" makes independent copies; mode="instance" makes live instances that mirror the source visual (editing the source updates them). count = number of NEW copies, each offset by (offsetX, offsetY) from the last.

Lay out copies of a layer in a pattern: "linear" (row/column via moveX/moveY), "grid" (columns×rows), "radial" (count around a circle: radius + angles), or "path" (distribute along a path layer). count includes the source. cloneMode copy|instance.

Create a bezier path layer from an array of [x,y] points. role="visual" draws a stroke; role="motion" is an invisible guide for assign_motion_path. Points are in layer-local px; set x/y to position the path.

Make a layer travel along a path layer (followPath). Set animateMs to auto-animate progress 0→1 over that duration. orientToPath rotates the layer to face the path tangent.

Reveal only part of a layer's stroke (line-draw / progress effect). start/end/offset are 0–1. Animate the reveal by keyframing layers..style.stroke.trim.end.

Create an editable spline primitive (circle/ellipse/rectangle/line/arc/donut/ngon/star). Use over add_layer shapes when the user wants an editable vector path (points/handles). Each kind takes its own geometry params (radius, sides, angles…).

Create ANY registered object kind, including shapes, text, group, media, spline, path, repeater or particle emitter. patch is a Partial. Discover kinds and properties with get_capabilities.

Patch any Layer fields: text, typography, transforms, effects, masks, repeater, visibility, stroke, geometry or particle configuration. Nested objects replace their existing value; read describe_layer first.

Set timeline duration, looping, pingPong, autoplay, work area, layer membership, markers, segments or events.

Duplicate an animation including keyframes, curves, modifiers, events and segments with a new timeline id.

Delete one timeline. Refuses timelines referenced by state machines.

Add or replace keyframes on an explicit timeline and layer property. Supports customBezier with {type:"customBezier",bezier:{cx1,cy1,cx2,cy2}}. Easing belongs to the starting keyframe.

Set track fields: keyframes, outOfRange, easeCurve, timeWarp, multiplierCurve, multiplierAmplitude, procedural waveform/noise controller, or complete modifier stack.

Remove an animation track from an explicit timeline.

Add a track modifier: sine, pulse, quantize, offset, scale, clamp, wave, noise, fractalNoise, jitter, timeWarp, bounce, elastic, overshoot, decay, spring.

Bake procedural animation/modifiers into editable linear keyframes.

Update emitter and particle settings, gradients, physics and lifetime properties.

Add/update/remove parameters, triggers, bindings, parameterWires or stateMachines by id. Use for advanced guards, transitions, formula wiring and runtime behavior.

List all animations, their duration, loop settings, tracks, segments and events.

Group selected layer ids in one undoable operation.

Ungroup a group and preserve children transforms and animation.

List explicitly connected Chorono editor tabs. Use sessionId when several tabs are open.

Discover all tools, object kinds, particle presets, limits and the exact script API.

Read the live editor scene plus revision, selected timeline and playhead. Read before editing existing work.

Execute synchronous JavaScript in isolated QuickJS. Only scene API is available; no Node, DOM, fetch, imports or filesystem. All edits are atomic. dryRun returns a planId which apply_script_plan commits without rerunning code.

Commit a previously prepared script plan exactly once, retaining generated object ids. Refuses a stale scene revision.

Apply ordered native tools atomically as ONE undo step. run_script and transport/file tools cannot be nested here.

Return an actual PNG frame. With no timeMs/timelineIds/parameters, captures the current live state including state machines. For deterministic time-based state-machine previews specify timelineIds. parameters overrides values for this frame only.

Play, pause, stop or seek the editor; select a timeline and set speed. timelineIds isolates animations in the live viewport; [] restores all animations.

Set live runtime parameters and dispatch a state-machine event. Events enable runtime test ticks so transitions/blends work while paused; testMode:false stops test ticks.

Read current runtime parameters, state-machine states, active timelines and playback state.

Evaluate timelines, bindings, parameter wiring and runtime parameters at a requested time. Returns property values without rendering pixels.

Undo one editor transaction.

Redo one editor transaction.

Save a portable scene JSON with local blob media embedded. Files stay inside the configured project directory. Returns exact path, bytes, revision and hash.

List saved project files inside the project directory.

Load a saved project by file name into the current editor as one undoable change.

Save validated and optimized runtime JSON in the export directory.

Save an SVG export using the existing vector exporter.

Render a frame sequence ZIP using the editor. Bounded to 300 frames per call. Does not include audio.

Import a media asset supplied as base64 file content using the existing import pipeline. No arbitrary local paths or server-side URL fetches.

Validate scene structure and return runtime-export diagnostics.