Driving Actors and the World

The Actors/World toolsets let the agent populate and edit your level: spawn actors, move and rotate them, attach components, query what exists, and clean up. This is usually the first thing people try, because it gives immediate, visible results in the viewport.

What the agent can do

• Spawn actors from a class or asset path (static meshes, lights, blueprints, empty actors) at a given location/rotation/scale.
• Transform actors — set or offset location, rotation, and scale; attach one actor to another.
• Select and query — list actors in the level, filter by class or name, read back an actor's transform and components.
• Edit components — add components to an actor and set their properties.
• Delete actors you no longer need.

Because these are reflected from the engine, the exact tool names follow the Verb+Noun pattern (for example a spawn tool and a transform tool). Ask the agent or call describe_toolset to see the precise names and parameters for your engine version.

Typical workflows

Block out a scene

Just describe it. For example:

"Spawn a floor plane at the origin, then place five cube static meshes in a row 200 units apart, 100 units above the floor."

The agent will discover the spawn and transform tools, spawn the plane, then loop the cubes into position. Everything appears live in the viewport.

Arrange and parent

"Group those cubes under a new empty actor called CubeRow and rotate the whole group 45 degrees around Z."

The agent spawns an empty actor, attaches the cubes to it, then rotates the parent — the children follow.

Inspect before acting

When a task depends on the current state, the agent reads first:

"List every PointLight in the level and tell me which ones are brighter than 5000 lumens."

It queries actors of that class, reads each light's intensity, and reports back — no changes made.

Tips

• Use full content paths. Spawning from an asset wants a path like /Game/Meshes/SM_Cube or /Engine/BasicShapes/Cube. The agent can call the Asset toolset's FindAssets first if it does not know the exact path.
• Coordinates are Unreal units (cm). "Two meters up" is +200 on Z.
• Save when you are happy. Spawning actors marks the level dirty but does not save it. Use the Level toolset's SaveCurrentLevel (or ask the agent to save) to persist the result.
• In a Multi-User session, saves are sandboxed. If you are collaborating in a Concert session, save reusable changes from a non-session editor — see the Multi-User guide and the levels notes for the sandbox gotcha.

Example via call_tool

In the default tool-search mode the agent reaches a spawn tool through the meta-tools:

{ "method": "tools/call", "params": {
    "name": "call_tool",
    "arguments": {
      "tool": "SpawnActor",
      "args": {
        "assetPath": "/Engine/BasicShapes/Cube",
        "location": { "x": 0, "y": 0, "z": 100 }
      }
    } } }

Tool and parameter names above are illustrative — confirm them with describe_toolset for the World/Actors toolset in your editor.