Quickstart: Claude Code

Claude Code can read, write, and manage files on OpenTusk directly through MCP tools — no SDK code required. This guide gets you from zero to “save this file to OpenTusk” in about 3 minutes.

Note

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

What you’ll set up

Claude Code
  ↕ MCP (stdin/stdout)
OpenTusk CLI (opentusk mcp serve)
  ↕ OpenTusk SDK
OpenTusk API → Hot Cache → Walrus Network

Claude Code talks to the OpenTusk MCP server, which runs as a local subprocess. The MCP server handles authentication, uploads, downloads, encryption, and all 34 storage operations on your behalf.

Setup

Option A: Invite code (recommended)

The fastest way — create an invite code, then redeem it to set up the agent:

1. Create an invite code

   opentusk invite create --name "claude-code"

   Copy the invite code (otinv_...) — it’s single-use and expires in 1 hour.

2. Redeem the code and install MCP config

   opentusk login --invite-code otinv_abc123...
   opentusk mcp install-config --target claude-code

   This generates a Sui keypair, creates an API key, and writes .mcp.json with everything configured.

3. Start a new Claude Code session

   Open Claude Code in your project directory. Try:

   “List my OpenTusk vaults”

Option B: Manual API key

If you already have an API key and are logged in:

1. Install the MCP config

   opentusk mcp install-config --target claude-code

2. Start a new Claude Code session

   Open Claude Code in your project directory. You should see OpenTusk’s tools available.

Try it out

Here are a few things to ask Claude Code once the MCP server is connected:

Prompt	What happens
”Create a vault called ‘project-docs‘“	Calls opentusk_vault_create with visibility public
”Upload README.md to my project-docs vault”	Calls opentusk_file_upload — reads from disk, uploads to OpenTusk
”Save this conversation summary to OpenTusk”	Calls opentusk_file_create — creates a file from inline content
”Download the latest report from OpenTusk”	Calls opentusk_file_download — writes to your local filesystem
”Back up the src/ directory to OpenTusk”	Uploads each file, organizing into folders
”What’s my storage usage?”	Calls opentusk_account_info — shows plan, quota, and usage

Add the SKILL.md (recommended)

The SKILL.md teaches Claude how to use OpenTusk well — when to create vaults, how to organize files, which workflows to follow. It loads into Claude’s context automatically.

mkdir -p .claude/skills/opentusk && curl -sL \
  https://docs.opentusk.ai/skills/SKILL.md \
  -o .claude/skills/opentusk/SKILL.md

With the SKILL.md installed, Claude knows patterns like:

• Project backup — zip and upload your project to a vault
• Conversation memory — persist context across sessions
• Artifact storage — save generated code, reports, or images
• Multi-agent sharing — use shared vaults to pass data between agents

Shared vaults

If you set up via invite code (Option A), Claude Code already has a Sui keypair and can work with shared vaults. Just add its address as a vault member:

# Find the agent's Sui address (shown during invite redemption, or in Settings → API Keys)
# Then grant access to a shared vault
opentusk vault members add <vault-id> <agent-sui-address>

If you set up via manual API key (Option B), you’ll need to store a Sui key first:

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

Either way, Claude can now upload to and download from shared vaults with end-to-end encryption. The MCP server handles SEAL encrypt/decrypt transparently.

Troubleshooting

Symptom	Fix
Tools not showing up	Restart Claude Code — it reads .mcp.json at session start
”Command not found”	Run opentusk mcp install-config again — it writes absolute paths
”Invalid API key”	Verify with opentusk whoami, or create a new key at app.opentusk.ai
”SEAL encryption not available”	Run opentusk account setup-sui <key> then reinstall the MCP config
File stuck in “rehydrating”	Cold files take a moment to fetch from Walrus — try the download again in a few seconds

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.

CLI reference Full command reference.