name: package-add description: Install a Unity package from the registry, a Git URL, or a local path. Modifies manifest.json and triggers package resolution; may also trigger a domain reload — the final result is delivered after the reload via the request's requestId. Use 'package-search' / 'package-list' for discovery first.

Package Manager / Add

Install a package from the Unity Package Manager registry, Git URL, or local path. This operation modifies the project's manifest.json and triggers package resolution. Note: Package installation may trigger a domain reload. The result will be sent after the reload completes. Use 'package-search' tool to search for packages and 'package-list' to list installed packages.

packageId formats

• Plain package ID: com.unity.textmeshpro (installs latest compatible version).
• Pinned version: com.unity.textmeshpro@3.0.6.
• Git URL: https://github.com/user/repo.git.
• Git URL with branch/tag: https://github.com/user/repo.git#v1.0.0.
• Local path: file:../MyPackage.

Processing model

Returns Processing immediately with the supplied requestId. Once Client.Add completes, a follow-up result is delivered: success → SchedulePostDomainReloadNotification (delivers after the reload finishes), failure → an immediate error notification with the underlying Unity error message.

How to Call

unity-mcp-cli run-tool package-add --input '{
  "packageId": "string_value"
}'

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

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

Or pipe via stdin (recommended):

unity-mcp-cli run-tool package-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": {
    "packageId": {
      "type": "string"
    }
  },
  "required": [
    "packageId"
  ]
}

Output

This tool does not return structured output.