Quickstart: Claude Desktop

Claude Desktop can read, write, and manage files on OpenTusk through MCP tools. Because Claude Desktop runs in a sandbox without filesystem access, it uses inline content tools (opentusk_file_create and opentusk_file_read) instead of disk-based upload/download.

Note

Need to install the CLI first? See Install & Setup.

Setup

1. Install the MCP config

   opentusk mcp install-config --target claude-desktop

   This writes the MCP server configuration to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) with absolute paths to the opentusk binary.

2. Restart Claude Desktop

   Quit and reopen Claude Desktop. The OpenTusk tools should appear in the tools menu.

3. Try it out

   “Create a vault called ‘notes’ and save a summary of today’s conversation”

Shared vault access

To enable SEAL encryption for shared vaults, add your Sui private key:

opentusk account setup-sui suiprivkey1...
opentusk mcp install-config --target claude-desktop  # re-install to embed the key

Sandbox-friendly tools

Claude Desktop can’t write to disk, so use these tools instead:

Use case	Tool
Save content to OpenTusk	opentusk_file_create (pass content inline)
Read a file from OpenTusk	opentusk_file_read (returns content inline)

The opentusk_file_upload and opentusk_file_download tools require filesystem access and won’t work in Claude Desktop’s sandbox.

Troubleshooting

Symptom	Fix
Tools not appearing	Restart Claude Desktop — it reads config at launch
”Command not found”	Re-run opentusk mcp install-config --target claude-desktop for absolute paths
”Invalid API key”	Verify with opentusk whoami

Next steps

MCP tools reference All 34 tools with parameters and examples.

Shared vaults Multi-party encrypted collaboration.

Encryption How SEAL end-to-end encryption works.