GameObject / Component / Add

Add Component to GameObject in opened Prefab or in a Scene. Use 'gameobject-find' tool to find the target GameObject first. Use 'gameobject-component-list-all' tool to find the component type names to add.

Inputs

• componentNames — list of component type names. Each entry may be a fully-qualified type name (preferred) or a bare class name (resolved via fallback to AllComponentTypes).
• gameObjectRef — the target GameObject. Required.

Behavior

Per-name errors (unknown type, type not assignable to UnityEngine.Component, add-failed/duplicate) are accumulated in response.Errors / response.Warnings instead of throwing, so a single bad name does not abort the whole batch. Successful additions populate response.AddedComponents with ComponentDataShallow snapshots.

How to Call

unity-mcp-cli run-tool gameobject-component-add --input '{
  "componentNames": "string_value",
  "gameObjectRef": "string_value"
}'

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

unity-mcp-cli run-tool gameobject-component-add --input-file args.json

Or pipe via stdin (recommended):

unity-mcp-cli run-tool gameobject-component-add --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
componentNames	any	Yes	Full name of the Component. It should include full namespace path and the class name.
gameObjectRef	any	Yes	Find GameObject in opened Prefab or in the active Scene.

Input JSON Schema

{
  "type": "object",
  "properties": {
    "componentNames": {
      "$ref": "#/$defs/System.String-1"
    },
    "gameObjectRef": {
      "$ref": "#/$defs/AIGD.GameObjectRef"
    }
  },
  "$defs": {
    "System.String-1": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "System.Type": {
      "type": "string"
    },
    "AIGD.GameObjectRef": {
      "type": "object",
      "properties": {
        "instanceID": {
          "type": "integer",
          "description": "instanceID of the UnityEngine.Object. If it is '0' and 'path', 'name', 'assetPath' and 'assetGuid' is not provided, empty or null, then it will be used as 'null'. Priority: 1 (Recommended)"
        },
        "path": {
          "type": "string",
          "description": "Path of a GameObject in the hierarchy Sample 'character/hand/finger/particle'. Priority: 2."
        },
        "name": {
          "type": "string",
          "description": "Name of a GameObject in hierarchy. Priority: 3."
        },
        "assetType": {
          "$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": "Find GameObject in opened Prefab or in the active Scene."
    }
  },
  "required": [
    "componentNames",
    "gameObjectRef"
  ]
}

Output

Output JSON Schema

{
  "type": "object",
  "properties": {
    "result": {
      "$ref": "#/$defs/AIGD.AddComponentResponse"
    }
  },
  "$defs": {
    "System.Collections.Generic.List(AIGD.ComponentDataShallow)": {
      "type": "array",
      "items": {
        "$ref": "#/$defs/AIGD.ComponentDataShallow"
      }
    },
    "AIGD.ComponentDataShallow": {
      "type": "object",
      "properties": {
        "instanceID": {
          "type": "integer"
        },
        "typeName": {
          "type": "string"
        },
        "isEnabled": {
          "type": "string",
          "enum": [
            "False",
            "True",
            "NA"
          ]
        }
      },
      "required": [
        "instanceID",
        "isEnabled"
      ]
    },
    "System.Collections.Generic.List(System.String)": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "AIGD.AddComponentResponse": {
      "type": "object",
      "properties": {
        "AddedComponents": {
          "$ref": "#/$defs/System.Collections.Generic.List(AIGD.ComponentDataShallow)",
          "description": "List of successfully added components."
        },
        "Messages": {
          "$ref": "#/$defs/System.Collections.Generic.List(System.String)",
          "description": "List of success messages for added components."
        },
        "Warnings": {
          "$ref": "#/$defs/System.Collections.Generic.List(System.String)",
          "description": "List of warnings encountered during component addition."
        },
        "Errors": {
          "$ref": "#/$defs/System.Collections.Generic.List(System.String)",
          "description": "List of errors encountered during component addition."
        }
      }
    }
  },
  "required": [
    "result"
  ]
}