GET /snapshot

Since 0.6

Response

Everything needed to restore the world to this frame.

Field	Type	Present	Description
`frame`	`integer`	always	The frame this state was captured at.
`time`	`number`	always	Simulated seconds since the scene loaded. `frame` multiplied by the fixed timestep; carried so a snapshot lines up with the `time` on an event without the client doing arithmetic.
`rng_seed`	`integer`	always	The deterministic RNG seed in effect.
`entities`	`EntityStateView[]`	always	Every entity's restorable state.
`hud`	`Props`	always	HUD fields the scene's `hud` components are showing. Values are strings or numbers; a field with no value is omitted rather than set to null.
`goals`	`GoalStateView[]`	always	Goal progress, in declaration order.
`opaque`	`OpaqueState`	sometimes	Solver state the physics backend cannot rebuild from transforms and velocities alone — contact islands, sleeping flags, warm-start impulses.
`session_paused`	`boolean`	sometimes	Whether `ctx.session.pause()` was holding the world. Absent when it was not. A held world counts frames without advancing `time`, so a capture taken after a pause has `time` behind `frame` × the timestep, and a restore keeps that `time` rather than recomputing it.

One entity's restorable state.

Field	Type	Present	Description
`id`	`string`	always	The entity's stable scene id.
`name`	`string`	always	Human-readable label, so a snapshot reads without a second call to `/entities`.
`tags`	`Tags`	sometimes	Scene tags. Omitted when the entity has none.
`position`	`number[3]`	always	World-space position.
`rotation`	`number[4]`	always	World-space rotation, `[x, y, z, w]`.
`scale`	`number[3]`	always	Local scale.
`velocity`	`Velocity`	sometimes	Linear and angular velocity. Absent for an entity with no rigid body, which is not the same thing as a rigid body at rest.
`script`	`ScriptStateView`	sometimes	The behavior's `ctx.state`, if it has one.
`anim`	`AnimStateView`	sometimes	Animator playhead, if it has one.
`overrides`	`{ string: Props }`	sometimes	What a behavior has written over this entity's components with `entity.set`, by component type. Omitted for an entity nothing has written to, which is almost all of them.
`reparent`	`ReparentView`	sometimes	Where a behaviour moved this entity with `entity.setParent`, when that is not the parent the scene gave it. Omitted for every entity still where the scene put it; a restore that omits it puts the entity back under the scene's parent.

One animator's restorable playhead.

Field	Type	Present	Description
`state`	`string`	always	Current state machine state.
`time`	`number`	always	Playhead in seconds.

A behaviour's reparent, as a snapshot carries it: the new parent's scene id, or null for the top of the scene.

Field	Type	Present	Description
`parent`	`string`	sometimes	The parent's scene id; `null` when the entity was moved to the top of the scene.

One behavior's restorable ctx.state.

Field	Type	Present	Description
`module`	`string`	always	The module specifier.
`state`	`Props`	always	`ctx.state`. Always an object.

Linear and angular velocity in world space.

Field	Type	Present	Description
`linear`	`number[3]`	always	Metres per second, `[x, y, z]`.
`angular`	`number[3]`	always	Radians per second about each world axis, `[x, y, z]`.

One goal's progress.

Field	Type	Present	Description
`id`	`string`	always	The goal's authored id, from its `goal` component.
`labelKey`	`string`	always	The string-table key for the goal's display text.
`order`	`integer`	sometimes	Declaration order, when the goal component gives one.
`reached`	`boolean`	always	Whether the goal has been reached.
`at_frame`	`integer`	sometimes	The frame it was reached on. Absent while it has not been.

Backend state a snapshot carries but nothing outside the backend interprets.

Field	Type	Present	Description
`backend`	`string`	always	Which backend wrote this, e.g. `rapier3d`. A snapshot is only restorable into the same one.
`version`	`integer`	always	The backend's format version. A mismatch means the blob cannot be restored.
`data`	`string`	always	The blob, base64.

curl "http://127.0.0.1:7700/snapshot"

Start a server with argus run --serve; the port is --port (7700 by default). The request and response fields are in the query API guide.