quackr-mcp

Quackr MCP Server

Official MCP server for Quackr — virtual phone numbers for SMS verification and OTP receipt. Use Claude (or any MCP-compatible client) to check pricing and inventory, purchase temporary numbers, and read incoming SMS programmatically.

• npm: quackr-mcp — npx -y quackr-mcp
• Hosted endpoint: https://mcp.quackr.io/
• Transport: Streamable HTTP
• Auth: Authorization: Bearer YOUR_API_KEY header

Tools

Tool	Description
get-balance	Get the current account balance in USD
get-pricing	Get phone number rental pricing for a specific country
get-inventory	Check available phone number inventory for a country
purchase-number	Purchase a temporary number for receiving SMS (deducts from balance)
check-sms	Check SMS messages received on a rented number
list-active-numbers	List all currently active (rented) numbers on the account

Getting an API Key

• Sign in at quackr.io
• Open your profile page
• Copy the API key from the API section

Install via npm

The quackr-mcp package is a thin stdio launcher that bridges any stdio MCP client to the hosted Quackr endpoint. It needs Node.js 18+ — no separate install required, npx fetches it on first run.

{
  "mcpServers": {
    "quackr": {
      "command": "npx",
      "args": ["-y", "quackr-mcp"],
      "env": {
        "QUACKR_API_KEY": "YOUR_API_KEY_HERE"
      }
    }
  }
}

You can also pass the key as a flag instead of an env var: npx -y quackr-mcp --api-key YOUR_API_KEY_HERE.

Claude Code Setup

Remote (recommended) — connect directly to the hosted endpoint. Add to your ~/.claude.json (or a project .mcp.json):

{
  "mcpServers": {
    "quackr": {
      "type": "http",
      "url": "https://mcp.quackr.io/",
      "headers": {
        "Authorization": "Bearer YOUR_API_KEY_HERE"
      }
    }
  }
}

Or via the CLI:

claude mcp add --transport http quackr https://mcp.quackr.io/ --header "Authorization: Bearer YOUR_API_KEY_HERE"

Claude Desktop Setup

Claude Desktop's JSON config only supports local (stdio) servers. Use the npm launcher (see Install via npm) by adding the npx quackr-mcp config above to claude_desktop_config.json, then restart Claude Desktop.

Alternatively, add Quackr as a remote connector: Settings → Connectors → Add custom connector, enter https://mcp.quackr.io/, and add an Authorization header with the value Bearer YOUR_API_KEY.

Other MCP Clients

Any client supporting remote Streamable HTTP MCP servers with custom headers works. Point it at https://mcp.quackr.io/ and pass your key via the Authorization: Bearer YOUR_API_KEY header.

REST API

Quackr also exposes a full REST API at https://api.quackr.io/ — see api.quackr.io/swagger.json for the full spec. Same x-api-key auth.

Support

• Website: quackr.io
• Issues: file in this repo
• Email: [e-mail]

License

MIT — see LICENSE.