io.prefabapp/prefab
List, create and deploy your Prefab project templates from any MCP agent.
Open source Open in the app JSON README (API)
About
List, create and deploy your Prefab project templates from any MCP agent.
Details
- Kind
- MCP servers
- Topic
- Cloud & DevOps
- Publisher
- io.prefabapp
- Origin
- official
- Category
- ferramentas
- Transport
- local
- Version
- 0.1.1
- Last push
- 2026-08-25T14:44:00Z
- Repository state
- ativo
- Language
- JavaScript
- License
- MIT
- Added
- 2026-08-29 04:01:45
- Updated
- 2026-08-29 04:01:45
- Origin id
io.prefabapp/prefab
README
# prefab-mcp
An MCP server for [Prefab](https://www.prefabapp.io), so an agent can see your templates and
deploy one for you.
"Set up a new client folder for Northwind, autumn campaign, on my Desktop"
## What it exposes
| Tool | Does |
| --- | --- |
| `list_templates` | Every template, what it creates, what it asks for |
| `describe_template` | One template in full: structure, placeholders, actions |
| `preview_deploy` | What a deploy would create, and what values are still missing. Creates nothing |
| `deploy_template` | Creates the folders, filling in the values given |
| `list_watched_folders` | Folders Prefab is watching, and the rules on them |
| `list_globals` | Library-wide placeholders, actions and value presets |
## Setting it up
Works with any client that speaks MCP over stdio.
**As a bundle** - download `prefab.mcpb` from the
[releases page](https://github.com/davidjaykelly/prefab-mcp/releases) and double-click it. Clients
that install MCP bundles, Claude Desktop among them, bring their own Node, so there is nothing else
to install.
**From the command line** (Claude Code, and anything with the same idea):
claude mcp add prefab -- npx -y prefab-mcp
**In a config file** - Cursor, Zed, and most others:
```json
{
"mcpServers": {
"prefab": { "command": "npx", "args": ["-y", "prefab-mcp"] }
}
}
```
Then switch on **Let agents and scripts control Prefab** in Prefab's Settings ▸ Permissions. It is
off by default; reading your templates works without it, creating and deploying does not.
That switch arrives in **Prefab 1.1.6**. On an earlier version the reading tools work and the rest
say so.
Requires macOS, Prefab installed and opened once, and Node 18+ (except for the `.mcpb` route).
## How it works
Prefab is sandboxed and has no network access, so it cannot host anything. This server runs beside
it instead: it **reads** the library straight out of the app group
(`~/Library/Group Containers/group.VFDG327T66.prefab`) and **asks the app to deploy** through the
same `prefab://` URL the Finder extension uses. Two consequences worth knowing:
- **Prefab has to be running** for a deploy. Reading works either way.
- **The destination has to be a folder Prefab has been granted.** macOS keeps a sandboxed app out
of your folders until you point it at one. `preview_deploy` and `deploy_template` both check
first and say so, rather than leaving a permission dialog on screen that an agent cannot answer.
Grant folders in Prefab, under Settings ▸ Permissions.
Nothing here writes to Prefab's library. The app owns those files, and editing them behind its
back would be overwritten the next time it saves.
## Development
npm test # checks placeholder resolution matches the app's Swift, case for case
npm run try '[["list_templates",{}]]' # call a tool the way a client does
`src/resolve.js` is a deliberate duplicate of `RenamePattern.swift`. If you change one, change the
other - `npm test` compiles the Swift and compares the two.