Claude Desktop disables installation if no system python detected, even with uv installed

[taylorwilsdon]

A DXT‑packed Python MCP that uses uv as its runtime installs and runs fine from the command line (uv run main.py) but Claude Desktop*refuses to install the same package, reporting it as “incompatible.”

manifest.json

---

manifest.json excerpt

{
  "server": {
    "type": "python",
    "entry_point": "main.py",
    "mcp_config": {
      "command": "uv",
      "args": [
        "run",
        "--directory",
        "${__dirname}",
        "python",
        "${__dirname}/main.py"
      ],
      "env": {
        // ...
      }
    }
  }
}

User has confirmed uv installation and can run the MCP with uv run main.py on the same system, but claude desktop won't let them install saying it's incompatible.

Expected behavior

• claude desktop install path/to/google_workspace_mcp.dxt should detect the python / uv runtime declared above and install without complaints—exactly as running uv run main.py does on the same machine.

Ref related issue here: taylorwilsdon/google_workspace_mcp#120

[joan-anthropic]

hi! could you try this proposed approach to python-based MCPBs (manifest server.type = uv, include a pyproject.toml with dependency requirements but do not actually bundle your dependencies in the .mcpb itself - and send us a link to the .mcpb you're trying to test? We're working out the rough edges here and this will be a helpful validation point :)

[bryan-anthropic]

Thanks for the detailed report. As Joan noted, MCPB v0.4 introduced server.type = "uv" which resolves this by telling Claude Desktop to use uv for dependency management rather than requiring system Python. This avoids the incompatibility check that was blocking installation.

If you run into issues with the uv server type, feel free to open a new issue.

@joan-anthropic @MarshallOfSound — This appears addressed by v0.4. Recommend closing.