personio-mcp-server

The server correctly handles API credentials via environment variables and uses an HTTP client (axios) with interceptors for robust error handling and token management. Input validation for tool arguments is present through `inputSchema` definitions and handler-level checks, primarily focusing on types and presence. No `eval` or direct command injection vectors were found. A minor potential concern is the `upload_document` tool, which accepts base64 file content and a file name but lacks explicit server-side validation of file types before forwarding to the Personio API. This could potentially allow uploading files with inappropriate extensions if the Personio API itself is not strict. The project includes a `SECURITY.md` with good practices.