@cryptoapis-io/mcp-prepare-transactions

MCP server for Crypto APIs Prepare Transactions product. Build unsigned EVM transactions for native coin transfers, fungible token transfers, and NFT transfers.

> API Version: Compatible with Crypto APIs version 2024-12-12

Features

• Prepare native coin transfer transactions (from address)
• Prepare fungible token (ERC-20) transfer transactions
• Prepare NFT (ERC-721) transfer transactions
• Returns unsigned transaction hex ready for signing with `@cryptoapis-io/mcp-signer`

Prerequisites

• Node.js 18+
• Crypto APIs account and API key (sign up | get API key)

Installation

npm install @cryptoapis-io/mcp-prepare-transactions

Or install all Crypto APIs MCP servers: `npm install @cryptoapis-io/mcp`

Usage

# Run with API key
npx @cryptoapis-io/mcp-prepare-transactions --api-key YOUR_API_KEY

# Or use environment variable
export CRYPTOAPIS_API_KEY=YOUR_API_KEY
npx @cryptoapis-io/mcp-prepare-transactions

# HTTP transport
npx @cryptoapis-io/mcp-prepare-transactions --transport http --port 3000 --api-key YOUR_API_KEY

Claude Desktop

Add to your Claude Desktop config (`~/Library/Application Support/Claude/claude_desktop_config.json` on macOS, `%APPDATA%\Claude\claude_desktop_config.json` on Windows):

{
  "mcpServers": {
    "cryptoapis-prepare-transactions": {
      "command": "npx",
      "args": ["-y", "@cryptoapis-io/mcp-prepare-transactions"],
      "env": {
        "CRYPTOAPIS_API_KEY": "your_api_key_here"
      }
    }
  }
}

Cursor

Add to `.cursor/mcp.json` (project) or `~/.cursor/mcp.json` (global):

{
  "mcpServers": {
    "cryptoapis-prepare-transactions": {
      "command": "npx",
      "args": ["-y", "@cryptoapis-io/mcp-prepare-transactions"],
      "env": {
        "CRYPTOAPIS_API_KEY": "your_api_key_here"
      }
    }
  }
}

MCP Inspector

npx @modelcontextprotocol/inspector npx @cryptoapis-io/mcp-prepare-transactions --api-key YOUR_API_KEY

n8n

1. Start the server in HTTP mode:

npx @cryptoapis-io/mcp-prepare-transactions --transport http --port 3000 --api-key YOUR_API_KEY

2. In your n8n workflow, add an AI Agent node

3. Under Tools, add an MCP Client Tool and set the URL to `http://localhost:3000/mcp`

> All servers default to port 3000. Use `--port` to assign different ports when running multiple servers.

Available Tools

`prepare_transactions_evm`

Prepare unsigned EVM transactions.

CLI Arguments

HTTP API Key Modes

When using HTTP transport, the server supports two API key modes:

• With `--api-key`: The key is used for all requests. `x-api-key` request headers are ignored.
• Without `--api-key`: Each request must include an `x-api-key` header with a valid Crypto APIs key. This enables hosting a public server where each user provides their own key.

# Per-request key mode (multi-tenant)
npx @cryptoapis-io/mcp-prepare-transactions --transport http --port 3000
# Clients send x-api-key header with each request

> Stdio transport always requires an API key at startup.

Important: API Key Required

> Warning: Making requests without a valid API key — or with an incorrect one — may result in your IP being banned from the Crypto APIs ecosystem. Always ensure a valid API key is configured before starting any server.

Remote MCP Server

Crypto APIs provides an official remote MCP server with all tools available via HTTP Streamable transport at https://ai.cryptoapis.io/mcp. Pass your API key via the `x-api-key` header — no installation required.

License

MIT