/script-update-or-create
Write a `.cs` script file (create or overwrite) with the provided C# code. Validates syntax via Roslyn before write — invalid code is rejected with error details and the file is left untouched. Refreshes the AssetDatabase and delivers the final result via `requestId` after Unity
$ npx -y skills add IvanMurzak/Unity-MCP --skill script-update-or-create --agent claude-codeHow it fires
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/script-update-or-create
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Write a `.cs` script file (create or overwrite) with the provided C# code. Validates syntax via Roslyn before write — invalid code is rejected with error details and the file is left untouched. Refreshes the AssetDatabase and delivers the final result via `requestId` after Unity
SKILL.md
script-update-or-create.SKILL.mdname: script-update-or-create
description: Write a `.cs` script file (create or overwrite) with the provided C# code. Validates syntax via Roslyn before write — invalid code is rejected with error details and the file is left untouched. Refreshes the AssetDatabase and delivers the final result via `requestId` after Unity finishes the triggered compilation. Use 'script-read' to inspect existing content first.
Script / Update or Create
Updates or creates script file with the provided C# code. Does AssetDatabase.Refresh() at the end. Provides compilation error details if the code has syntax errors. Use 'script-read' tool to read existing script files first.
Inputs
- `filePath` — required `.cs` path.
- `content` — C# source. MUST pass `ScriptUtils.IsValidCSharpSyntax`.
- `requestId` — required for the processing/delivered-later contract.
Behavior
Creates any missing parent directories, writes the file, then calls `AssetDatabase.Refresh` and schedules a post-compilation notification so the final response is delivered after Unity finishes the recompile.
How to Call
unity-mcp-cli run-tool script-update-or-create --input '{
"filePath": "string_value",
"content": "string_value"
}'> For complex input (multi-line strings, code), save the JSON to a file and use: > ```bash > unity-mcp-cli run-tool script-update-or-create --input-file args.json > ``` > > Or pipe via stdin (recommended): > ```bash > unity-mcp-cli run-tool script-update-or-create --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 | |------|------|----------|-------------| | `filePath` | `string` | Yes | The path to the file. Sample: "Assets/Scripts/MyScript.cs". | | `content` | `string` | Yes | C# code - content of the file. |
Input JSON Schema
{
"type": "object",
"properties": {
"filePath": {
"type": "string"
},
"content": {
"type": "string"
}
},
"required": [
"filePath",
"content"
]
}Output
This tool does not return structured output.
Read more
name: script-update-or-create description: Write a `.cs` script file (create or overwrite) with the provided C# code. Validates syntax via Roslyn before write — invalid code is rejected with error details and the file is left untouched. Refreshes the AssetDatabase and delivers the final result via `requestId` after Unity finishes the triggered compilation. Use 'script-read' to inspect existing content first.
Script / Update or Create
Updates or creates script file with the provided C# code. Does AssetDatabase.Refresh() at the end. Provides compilation error details if the code has syntax errors. Use 'script-read' tool to read existing script files first.
Inputs
- `filePath` — required `.cs` path.
- `content` — C# source. MUST pass `ScriptUtils.IsValidCSharpSyntax`.
- `requestId` — required for the processing/delivered-later contract.
Behavior
Creates any missing parent directories, writes the file, then calls `AssetDatabase.Refresh` and schedules a post-compilation notification so the final response is delivered after Unity finishes the recompile.
How to Call
unity-mcp-cli run-tool script-update-or-create --input '{
"filePath": "string_value",
"content": "string_value"
}'> For complex input (multi-line strings, code), save the JSON to a file and use: > ```bash > unity-mcp-cli run-tool script-update-or-create --input-file args.json > ``` > > Or pipe via stdin (recommended): > ```bash > unity-mcp-cli run-tool script-update-or-create --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 | |------|------|----------|-------------| | `filePath` | `string` | Yes | The path to the file. Sample: "Assets/Scripts/MyScript.cs". | | `content` | `string` | Yes | C# code - content of the file. |
Input JSON Schema
{
"type": "object",
"properties": {
"filePath": {
"type": "string"
},
"content": {
"type": "string"
}
},
"required": [
"filePath",
"content"
]
}Output
This tool does not return structured output.
Get up and running in three steps: Install plugin — download the .unitypackage installer or run openupm add com.ivanmurzak.unity.mcp Alternative: npx unity-mcp-cli install-plugin ./MyUnityProject — see CLI documentation Pick an AI agent — Claude Code, Claude
Repo: IvanMurzak/Unity-MCP
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