assets-modify

name	assets-modify
description	Modify an asset file in the project. Use 'assets-get-data' first to inspect the asset structure before modifying. Not allowed to modify asset files in the 'Packages/' folder — modify them in 'Assets/'. Three modification surfaces are available (content, pathPatches, jsonPatch) — see the skill body for details.

Assets / Modify

Three modification surfaces

Use whichever fits the task:

1. content — full SerializedMember override (legacy, backwards compatible).
2. pathPatches — list of {path, value} pairs routed through Reflector.TryModifyAt.
3. jsonPatch — JSON Merge Patch routed through Reflector.TryPatch.

When more than one is supplied they run in this order: jsonPatch → pathPatches → content. At least one is required.

Path syntax

fieldName, nested/field, arrayField/[i], dictField/[key]. Leading #/ is stripped.

How to Call

unity-mcp-cli run-tool assets-modify --input '{
  "assetRef": "string_value",
  "content": "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 assets-modify --input-file args.json

Or pipe via stdin (recommended):

unity-mcp-cli run-tool assets-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
assetRef	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.
content	any	No	Optional. The asset content. It overrides the existing asset content (legacy path).
pathPatches	any	No	Optional. List of path-scoped patches routed through Reflector.TryModifyAt.
jsonPatch	any	No	Optional. JSON Merge Patch (RFC 7396, extended with [i]/[key] keys) routed through Reflector.TryPatch.

Input JSON Schema

{
  "type": "object",
  "properties": {
    "assetRef": {
      "$ref": "#/$defs/AIGD.AssetObjectRef"
    },
    "content": {
      "$ref": "#/$defs/com.IvanMurzak.ReflectorNet.Model.SerializedMember"
    },
    "pathPatches": {
      "$ref": "#/$defs/System.Collections.Generic.List(AIGD.PathPatch)"
    },
    "jsonPatch": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "type": "object",
          "additionalProperties": true
        }
      ]
    
  
   
     
       
    
     
       
       
         
           
           
        
         
           
           
        
         
           
           
        
         
           
           
        
      
       
        
      
       
    
     
       
       
         
      
    
     
       
       
         
           
           
        
         
           
           
        
         
           
        
         
           
           
             
             
          
           
        
         
           
           
             
             
          
           
        
      
       
        
      
       
    
     
       
       
         
           
           
        
         
           
           
        
      
    
     
       
       
         
      
    
  
   
    
  

Output

Output JSON Schema

{
  "type": "object",
  "properties": {
    "result": {
      "$ref": "#/$defs/System.String-1"
    }
  },
  "$defs": {
    "System.String-1": {
      "type": "array",
      "items": {
        "type": "string"
      }
    }
  },
  "required": [
    "result"
  ]
}