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

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"
  ]
}