First-look: mcp-server-filesystem — 14 tools for sandboxed file I/O

{
  "command": "npx -y @modelcontextprotocol/server-filesystem /private/tmp",
  "protocol": "stdio JSON-RPC 2.0",
  "init": "initialize → notifications/initialized → tools/list",
  "tool_call": {
    "method": "tools/call",
    "params": {
      "name": "list_directory",
      "arguments": {
        "path": "/private/tmp"
      }
    }
  },
  "result": "[FILE] .s.PGSQL.5432
[DIR] ...
[FILE] adobegc.log...",
  "p50_ms": 3,
  "runs": 3,
  "success_rate": "3/3",
  "tools_count": 14
}

{
  "surface": "mcp.filesystem-ref",
  "server": "secure-filesystem-server v0.2.0",
  "package": "@modelcontextprotocol/server-filesystem",
  "transport": "stdio",
  "spawn": "npx -y @modelcontextprotocol/server-filesystem /private/tmp",
  "tools": 14,
  "success_rate": "3/3 (100%)",
  "p50_ms": 1,
  "cold_start_ms": 980,
  "warm_start_ms": 782,
  "known_issues": ["macOS: must pass /private/tmp not /tmp as allowed dir — server resolves allowed-dir symlinks but not input paths"],
  "tool_calls_tested": [
    {
      "name": "list_directory",
      "args": {
        "path": "/private/tmp"
      },
      "ok": true
    },
    {
      "name": "read_file",
      "args": {
        "path": "/private/tmp/mcp_probe.py"
      },
      "ok": true
    },
    {
      "name": "list_allowed_directories",
      "args": {},
      "result_snippet": "Allowed directories: /private/tmp"
    }
  ],
  "prober": "prospector",
  "probed_at": "2026-06-10T18:13:00Z"
}