scene-set-active

name	scene-set-active
description	Mark an opened scene as the Editor's active scene (the one new GameObjects are added to and that's used as the default for many operations). Use 'scene-list-opened' to enumerate opened scenes first.

Scene / Set Active

Set the specified opened scene as the active scene. Use 'scene-list-opened' tool to get the list of all opened scenes.

Inputs

• sceneRef — AssetObjectRef pointing at a SceneAsset. The scene must already be opened.

Behavior

Resolves the SceneAsset, finds the matching opened scene (by name then by path), and calls EditorSceneManager.SetActiveScene. No-op if the scene is already active. Returns the post-call snapshot of opened scenes.

How to Call

unity-mcp-cli run-tool scene-set-active --input '{
  "sceneRef": "string_value"
}'

For complex input (multi-line strings, code), save the JSON to a file and use:

unity-mcp-cli run-tool scene-set-active --input-file args.json

Or pipe via stdin (recommended):

unity-mcp-cli run-tool scene-set-active --input-file - <<'EOF'
{"param": "value"}
EOF

Troubleshooting

If unity-mcp-cli is not found, either install it globally (npm install -g unity-mcp-cli) or use npx unity-mcp-cli instead. Read the /unity-initial-setup skill for detailed installation instructions.

Input

Name	Type	Required	Description
sceneRef	any	Yes	Reference to UnityEngine.Object asset instance. It could be Material, ScriptableObject, Prefab, and any other Asset. Anything located in the Assets and Packages folders.

Input JSON Schema

{
  "type": "object",
  "properties": {
    "sceneRef": {
      "$ref": "#/$defs/AIGD.AssetObjectRef"
    }
  },
  "$defs": {
    "System.Type": {
      "type": "string"
    },
    "AIGD.AssetObjectRef": {
      "type": "object",
      "properties": {
        "instanceID": {
          "type": "integer",
          "description": "instanceID of the UnityEngine.Object. If this is '0' and 'assetPath' and 'assetGuid' is not provided, empty or null, then it will be used as 'null'."
        },
        "assetType": {
          "$ref": "#/$defs/System.Type",
          "description": "Type of the asset."
        },
        "assetPath": {
          "type": "string",
          "description": "Path to the asset within the project. Starts with 'Assets/'"
        },
        "assetGuid": {
          "type": "string",
          "description": "Unique identifier for the asset."
        }
      },
      "required": [
        "instanceID"
      ],
      "description": "Reference to UnityEngine.Object asset instance. It could be Material, ScriptableObject, Prefab, and any other Asset. Anything located in the Assets and Packages folders."
    }
  },
  "required": [
    "sceneRef"
  ]
}

Output

Output JSON Schema

{
  "type": "object",
  "properties": {
    "result": {
      "$ref": "#/$defs/AIGD.SceneDataShallow-1"
    }
  },
  "$defs": {
    "AIGD.SceneDataShallow": {
      "type": "object",
      "properties": {
        "Name": {
          "type": "string"
        },
        "IsLoaded": {
          "type": "boolean"
        },
        "IsDirty": {
          "type": "boolean"
        },
        "IsSubScene": {
          "type": "boolean"
        },
        "IsValidScene": {
          "type": "boolean",
          "description": "Whether this is a valid Scene. A Scene may be invalid if, for example, you tried to open a Scene that does not exist. In this case, the Scene returned from EditorSceneManager.OpenScene would return False for IsValid."
        },
        "RootCount": {
          "type": "integer"
        },
        "path": {
          "type": "string",
          "description": "Path to the Scene within the project. Starts with 'Assets/'"
        },
        "buildIndex": {
          "type": "integer",
          "description": "Build index of the Scene in the Build Settings."
        },
        "instanceID": {
          "type": "integer",
          "description": "instanceID of the UnityEngine.Object. If this is '0', then it will be used as 'null'."
        }
      },
      "required": [
        "IsLoaded",
        "IsDirty",
        "IsSubScene",
        "IsValidScene",
        "RootCount",
        "buildIndex",
        "instanceID"
      ],
      "description": "Scene reference. Used to find a Scene."
    },
    "AIGD.SceneDataShallow-1": {
      "type": "array",
      "items": {
        "$ref": "#/$defs/AIGD.SceneDataShallow",
        "description": "Scene reference. Used to find a Scene."
      }
    }
  },
  "required": [
    "result"
  ]
}