gameobject-component-modify

name

gameobject-component-modify

description

Modify a specific Component on a GameObject in opened Prefab or in a Scene. Allows direct modification of component fields and properties without wrapping in GameObject structure. Use 'gameobject-component-get' first to inspect the component structure before modifying. Three modification surfaces (use whichever fits the task): 1. 'componentDiff' — full SerializedMember diff (legacy, backwards compatible). 2. 'pathPatches' — list of {path, value} pairs routed through Reflector.TryModifyAt; atomic per-path modification, multiple entries can target different depths. 3. 'jsonPatch' — a JSON Merge Patch (RFC 7396, extended with [i]/[key] notation) routed through Reflector.TryPatch; multiple fields at any depth in a single call. When more than one is supplied they run in this order: jsonPatch → pathPatches → componentDiff. At least one is required. Path syntax: 'fieldName', 'nested/field', 'arrayField/[i]', 'dictField/[key]'. Leading '#/' is stripped.

GameObject / Component / Modify

How to Call

unity-mcp-cli run-tool gameobject-component-modify --input '{
  "gameObjectRef": "string_value",
  "componentRef": "string_value",
  "componentDiff": "string_value",
  "pathPatches": "string_value",
  "jsonPatch": "string_value"
}'

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

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

Or pipe via stdin (recommended):

unity-mcp-cli run-tool gameobject-component-modify --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
gameObjectRef	any	Yes	Find GameObject in opened Prefab or in the active Scene.
componentRef	any	Yes	Component reference. Used to find a Component at GameObject.
componentDiff	any	No	Optional. The full component data to apply (legacy path). Should contain 'fields' and/or 'props' with the values to modify.
Only include the fields/properties you want to change.
Any unknown or invalid fields and properties will be reported in the response.
pathPatches	any	No	Optional. List of path-scoped patches routed through Reflector.TryModifyAt. Each entry targets one field/element/entry by path. Path syntax: 'fieldName', 'nested/field', 'arrayField/[i]', 'dictField/[key]'.
jsonPatch	string	No	Optional. JSON Merge Patch (RFC 7396, extended with [i]/[key] keys) routed through Reflector.TryPatch. Allows multiple fields at any depth to be updated in a single call. Use '$type' for compatible-subtype replacement.

Input JSON Schema

{
  "type": "object",
  "properties": {
    "gameObjectRef": {
      "$ref": "#/$defs/com.IvanMurzak.Unity.MCP.Runtime.Data.GameObjectRef"
    },
    "componentRef": {
      "$ref": "#/$defs/com.IvanMurzak.Unity.MCP.Runtime.Data.ComponentRef"
    },
    "componentDiff": {
      "$ref": "#/$defs/com.IvanMurzak.ReflectorNet.Model.SerializedMember"
    },
    "pathPatches": {
      "$ref": "#/$defs/System.Collections.Generic.List<com.IvanMurzak.Unity.MCP.Runtime.Data.PathPatch>"
    },
    "jsonPatch": {
      "type": "string"
    }
  },
  "$defs": {
    "System.Type": {
      "type": "string"
    },
    "com.IvanMurzak.Unity.MCP.Runtime.Data.GameObjectRef": {
      "type": "object",
      "properties": {
        "instanceID": {
          "type": "integer",
          "description": "instanceID of the UnityEngine.Object. If it is '0' and 'path', 'name', 'assetPath' and 'assetGuid' is not provided, empty or null, then it will be used as 'null'. Priority: 1 (Recommended)"
        },
        "path": {
          "type": "string",
          "description": "Path of a GameObject in the hierarchy Sample 'character/hand/finger/particle'. Priority: 2."
        },
        "name": {
          "type": "string",
          "description": "Name of a GameObject in hierarchy. Priority: 3."
        },
        "assetType": {
          "$ref": "#/$defs/System.Type",
          "description": "Type of the asset."
        },
        "assetPath": {
          "type": "string",
          "description": "Path to the asset within the project. Starts with 'Assets/'"
        },
        "assetGuid": {
          "type": "string",
          "description": "Unique identifier for the asset."
        }
      },
      "required": [
        "instanceID"
      ],
      "description": "Find GameObject in opened Prefab or in the active Scene."
    },
    "com.IvanMurzak.Unity.MCP.Runtime.Data.ComponentRef": {
      "type": "object",
      "properties": {
        "index": {
          "type": "integer",
          "description": "Component 'index' attached to a gameObject. The first index is '0' and that is usually Transform or RectTransform. Priority: 2. Default value is -1."
        },
        "typeName": {
          "type": "string",
          "description": "Component type full name. Sample 'UnityEngine.Transform'. If the gameObject has two components of the same type, the output component is unpredictable. Priority: 3. Default value is null."
        },
        "instanceID": {
          "type": "integer",
          "description": "instanceID of the UnityEngine.Object. If this is '0', then it will be used as 'null'."
        }
      },
      "required": [
        "index",
        "instanceID"
      ],
      "description": "Component reference. Used to find a Component at GameObject."
    },
    "com.IvanMurzak.ReflectorNet.Model.SerializedMemberList": {
      "type": "array",
      "items": {
        "$ref": "#/$defs/com.IvanMurzak.ReflectorNet.Model.SerializedMember"
      }
    },
    "com.IvanMurzak.ReflectorNet.Model.SerializedMember": {
      "type": "object",
      "properties": {
        "typeName": {
          "type": "string",
          "description": "Full type name. Eg: 'System.String', 'System.Int32', 'UnityEngine.Vector3', etc."
        },
        "name": {
          "type": "string",
          "description": "Object name."
        },
        "value": {
          "description": "Value of the object, serialized as a non stringified JSON element. Can be null if the value is not set. Can be default value if the value is an empty object or array json."
        },
        "fields": {
          "type": "array",
          "items": {
            "$ref": "#/$defs/com.IvanMurzak.ReflectorNet.Model.SerializedMember",
            "description": "Nested field value."
          },
          "description": "Fields of the object, serialized as a list of 'SerializedMember'."
        },
        "props": {
          "type": "array",
          "items": {
            "$ref": "#/$defs/com.IvanMurzak.ReflectorNet.Model.SerializedMember",
            "description": "Nested property value."
          },
          "description": "Properties of the object, serialized as a list of 'SerializedMember'."
        }
      },
      "required": [
        "typeName"
      ],
      "additionalProperties": false
    },
    "com.IvanMurzak.Unity.MCP.Runtime.Data.PathPatch": {
      "type": "object",
      "properties": {
        "Path": {
          "type": "string",
          "description": "Slash-delimited path to the target field/element/entry. Plain segment navigates a field or property (e.g. 'admin' or 'admin/name'). Use '[i]' for array/list index (e.g. 'planets/[0]/orbitRadius'). Use '[key]' for dictionary entry (e.g. 'config/[timeout]'). A leading '#/' is stripped automatically. Required."
        },
        "Value": {
          "$ref": "#/$defs/com.IvanMurzak.ReflectorNet.Model.SerializedMember",
          "description": "The new value to write at the path. Use the standard SerializedMember envelope: 'typeName' + 'value' for primitives, or nested 'fields'/'props' for complex types. Required — omitting it overwrites the target with a default empty SerializedMember."
        }
      }
    },
    "System.Collections.Generic.List<com.IvanMurzak.Unity.MCP.Runtime.Data.PathPatch>": {
      "type": "array",
      "items": {
        "$ref": "#/$defs/com.IvanMurzak.Unity.MCP.Runtime.Data.PathPatch"
      }
    }
  },
  "required": [
    "gameObjectRef",
    "componentRef"
  ]
}

Output

Output JSON Schema

{
  "type": "object",
  "properties": {
    "result": {
      "$ref": "#/$defs/com.IvanMurzak.Unity.MCP.Editor.API.Tool_GameObject+ModifyComponentResponse"
    }
  },
  "$defs": {
    "com.IvanMurzak.Unity.MCP.Runtime.Data.ComponentRef": {
      "type": "object",
      "properties": {
        "index": {
          "type": "integer",
          "description": "Component 'index' attached to a gameObject. The first index is '0' and that is usually Transform or RectTransform. Priority: 2. Default value is -1."
        },
        "typeName": {
          "type": "string",
          "description": "Component type full name. Sample 'UnityEngine.Transform'. If the gameObject has two components of the same type, the output component is unpredictable. Priority: 3. Default value is null."
        },
        "instanceID": {
          "type": "integer",
          "description": "instanceID of the UnityEngine.Object. If this is '0', then it will be used as 'null'."
        }
      },
      "required": [
        "index",
        "instanceID"
      ],
      "description": "Component reference. Used to find a Component at GameObject."
    },
    "com.IvanMurzak.Unity.MCP.Runtime.Data.ComponentDataShallow": {
      "type": "object",
      "properties": {
        "instanceID": {
          "type": "integer"
        },
        "typeName": {
          "type": "string"
        },
        "isEnabled": {
          "type": "string",
          "enum": [
            "False",
            "True",
            "NA"
          ]
        }
      },
      "required": [
        "instanceID",
        "isEnabled"
      ]
    },
    "System.String[]": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "com.IvanMurzak.Unity.MCP.Editor.API.Tool_GameObject+ModifyComponentResponse": {
      "type": "object",
      "properties": {
        "Success": {
          "type": "boolean",
          "description": "Whether the modification was successful."
        },
        "Reference": {
          "$ref": "#/$defs/com.IvanMurzak.Unity.MCP.Runtime.Data.ComponentRef",
          "description": "Reference to the modified component."
        },
        "Index": {
          "type": "integer",
          "description": "Index of the component in the GameObject's component list."
        },
        "Component": {
          "$ref": "#/$defs/com.IvanMurzak.Unity.MCP.Runtime.Data.ComponentDataShallow",
          "description": "Updated component information after modification."
        },
        "Logs": {
          "$ref": "#/$defs/System.String[]",
          "description": "Log of modifications made and any warnings/errors encountered."
        }
      },
      "required": [
        "Success",
        "Index"
      ]
    }
  },
  "required": [
    "result"
  ]
}