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Giving Claude Filesystem Access ​

Quick guide for setting up Claude Desktop to access your local filesystem.

Why This Matters ​

By default, Claude can't access your local files. Setting up filesystem access lets Claude:

  • Read files from your repo
  • Write/modify files directly
  • Run commands in your project directory
  • Work with your actual codebase instead of uploaded copies

Setup Steps ​

1. Open Claude Desktop Settings ​

  • Click "Claude" menu → "Settings" (or Cmd+,)

2. Go to Developer Tab ​

  • Look for "Developer" or "Advanced" settings

3. Enable MCP/Filesystem Access ​

  • Look for "Model Context Protocol" or "MCP Servers"
  • There should be a filesystem server option

4. Add Your Project Directory ​

Option A: Through UI

  • Add ~/GitHub/YOUR_PROJECT to allowed directories

Option B: Edit Config File

The MCP config is at:

~/Library/Application Support/Claude/claude_desktop_config.json

Edit it to add:

json
{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-filesystem", "/Users/YOUR_USERNAME/GitHub/YOUR_PROJECT"]
    }
  }
}

5. Restart Claude Desktop ​

After restarting, Claude will have access to your project directory.

What Claude Can Do After Setup ​

With filesystem access configured:

  • ✅ Read any file in your project
  • ✅ Write/modify files in the repo
  • ✅ Run commands like yarn docs:build
  • ✅ Create new files
  • ✅ Search through your codebase

Security Note ​

Claude will only have access to the specific directory you configure. It cannot access other parts of your filesystem unless you explicitly add them to the allowed directories list.

Verification ​

To test if it's working, ask Claude to:

  • Read a file: "Read the package.json file"
  • List directory: "List the files in src/lib"
  • Run a command: "Run yarn docs:build"

If Claude can do these things, the setup worked!

Troubleshooting ​

Disconnect error when restarting Claude Desktop

  • The error may appear on startup but filesystem access still works afterward
  • Test by asking Claude to read a file. If it works, ignore the error.

Config issues

  • Use "command": "npx" (not the full path to npx)
  • Check JSON syntax carefully — valid JSON has no trailing commas
  • Test the MCP server directly:
    bash
    npx -y @modelcontextprotocol/server-filesystem ~/GitHub/YOUR_PROJECT

"Can't cd to ~/GitHub/YOUR_PROJECT"

  • Filesystem access isn't configured yet
  • Try the manual config file method above

Commands still fail

  • Make sure you restarted Claude Desktop after editing config
  • Check that the path in the config is exactly right

Alternative: Manual Upload/Download ​

If you don't want to set up filesystem access, you can still work with Claude by:

  • Uploading specific files to the chat when needed
  • Claude creates files on its filesystem, then provides download links
  • You manually save downloaded files to your repo

This works but is slower and more manual than direct filesystem access.