Content
# cli2mcp.app
Turn any macOS command-line tool into a Model Context Protocol server — with no
Node, no Python, and no `npx` bootstrap. cli2mcp is a native SwiftUI app that
inspects a CLI's `--help`, infers an input schema, and hands you a ready-to-paste
MCP snippet for Claude Desktop or any other MCP client. A bundled stdio helper
does the actual wrapping at runtime, and ships inside the same `.app`.
<img width="2204" height="1708" alt="screenshot2026-05-26_15 39 22@2x" src="https://github.com/user-attachments/assets/d96d667f-b883-4507-8e44-1f744d6be749" />
## Why cli2mcp
- **Pick, copy, paste.** Choose a preset (`jq`, `rg`, `pandoc`, `sed`, `curl`,
`ffmpeg`, `yt-dlp`, or your own), copy the generated JSON, and paste it into
your MCP client. The snippet points directly at the helper inside the bundle:
`Cli2MCP.app/Contents/MacOS/cli2mcp-server`.
- **Verify before you trust.** A built-in health probe launches the same helper
your client will use, exchanges `initialize` and `tools/list`, and shows the
full stdio transcript — so you see exactly what an MCP client will see.
- **Self-contained.** Pure Swift, single bundle. No package manager, no
registry, no scripting runtime, no post-checkout download. If you have the
Swift toolchain, you can build it offline.
- **Safe by construction.**
- Tool-call positionals are appended after a POSIX `--` end-of-options
marker, so user-provided strings can never be reinterpreted as flags by
the wrapped CLI.
- Children launch via `Foundation.Process` with executable and argument
arrays — never shell command text.
- `--env-passthrough safe` forwards only essentials (`PATH`, `HOME`, `LANG`,
`TERM`, and standard XDG directory variables); `all` and `none` remain
explicit, and `--inherit-shell-env` can opt into a login-shell environment
when a preset needs it.
- Per-call timeout defaults to 60 seconds; `--max-concurrent N` caps
in-flight calls.
It's notarized to keep Apple happy.
Grab it from github releases. Put it in /Applications. Thats's it.
## What a snippet looks like
Snippets copied from the app use an absolute command path for the helper:
```json
{
"mcpServers": {
"jq": {
"command": "/Applications/Cli2MCP.app/Contents/MacOS/cli2mcp-server",
"args": ["jq", "--env-passthrough", "safe", "--max-concurrent", "4", "--timeout", "60000"]
}
}
}
```
If you move the app, reopen it from the new location and copy the snippet again
so the absolute helper path stays current.
## Build it yourself
```sh
cd mac && make test
make app
make sign-distribution SIGN_IDENTITY="Developer ID Application: Example, Inc. (TEAMID)"
make install
make reinstall
make run-app
```
`make app` produces `mac/build/Cli2MCP.app`, with both the SwiftUI executable
and `cli2mcp-server` copied into `Contents/MacOS/`.
See [`mac/README.md`](mac/README.md) for macOS app details.
## License
GNU Affero General Public License v3.0 only (`AGPL-3.0-only`). See
[`LICENSE`](LICENSE).
