title: MCP Server description: "Use CardZero in Claude Desktop, Cursor, VS Code via the official Model Context Protocol server."

The official cardzero-mcp package exposes 10 tools to any MCP-capable host: Claude Desktop, Cursor, VS Code, Cline, Continue, etc. The agent can manage wallets, send payments, run job lifecycles — all in natural language.

Tools available

| Tool | What it does | | --- | --- | | create_wallet | Create a CardZero wallet (returns claim key for Owner) | | get_balance | Read current USDC balance | | send_payment | Send USDC to an address (after user confirmation) | | pay_x402 | Pay an HTTP 402-protected resource | | list_payments | Recent payment history | | get_payment | Status of a specific payment by ID | | create_job | Create an ERC-8183 escrow Job | | fund_job | Lock budget USDC into Job escrow | | submit_job | Submit a deliverable hash (Provider side) | | get_job | Inspect Job state (no auth needed) |

Setup

Prerequisites

• Node.js 18+ (for npx)
• CardZero account — created via Quickstart
• API Key + Wallet ID — from your dashboard

Claude Desktop

Open ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows). Add:

{
  "mcpServers": {
    "cardzero": {
      "command": "npx",
      "args": ["-y", "cardzero-mcp"],
      "env": {
        "CARDZERO_API_KEY": "czapi_…",
        "CARDZERO_WALLET_ID": "wallet_…"
      }
    }
  }
}

Restart Claude Desktop completely (Cmd+Q, not just close).

Try: "What's my CardZero balance?" → Claude calls get_balance → answers.

Cursor

Cursor reads MCP config from ~/.cursor/mcp.json. Same JSON shape as Claude Desktop above.

After saving, Cursor → Settings → MCP → toggle CardZero on.

VS Code (with MCP extension)

Install the MCP extension. Open settings JSON, add the same mcpServers block.

Cline / Continue / other MCP clients

Same npx -y cardzero-mcp invocation; consult your client's docs for where to place the config.

Verifying it works

Once configured, ask the agent something the tool resolves:

"Show me my last 5 CardZero payments."

The agent should call list_payments and respond with a table. If it says "I don't have a tool for that," the MCP server isn't loading — see Troubleshooting below.

Tool behavior notes

• send_payment and pay_x402 should ask for confirmation. The SKILL prompts the agent to verify amount + recipient with the user before calling the tool. Don't override this.
• create_wallet returns a claim key which the agent should pass to the Owner verbatim. The key is one-time and expires in 7 days.
• get_payment and get_job are public — no auth required, useful for third-party verification.
• create_job requires v3 wallet. If you used v2, the call will return WALLET_VERSION_MISMATCH. Create a new v3 wallet.

Troubleshooting

Updating

# npx auto-fetches latest unless cached. To force latest:
rm -rf ~/.npm/_npx
# Then restart your MCP host.

Or pin a version in config:

"args": ["-y", "[email protected]"]

Latest version always at npmjs.com/package/cardzero-mcp.