Create webhook subscriptions for blockchain events (new block, confirmed transaction, address coins, token transfers, etc.)
List, get, activate, and delete existing subscriptions
Supports all major blockchains (EVM, UTXO, Solana, XRP)

Prerequisites

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

Installation

npm install @cryptoapis-io/mcp-blockchain-events

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

Usage

# Run with API key
npx @cryptoapis-io/mcp-blockchain-events --api-key YOUR_API_KEY

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

# HTTP transport
npx @cryptoapis-io/mcp-blockchain-events --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-blockchain-events": {
      "command": "npx",
      "args": ["-y", "@cryptoapis-io/mcp-blockchain-events"],
      "env": {
        "CRYPTOAPIS_API_KEY": "your_api_key_here"
      }
    }
  }
}

Cursor

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

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

MCP Inspector

npx @modelcontextprotocol/inspector npx @cryptoapis-io/mcp-blockchain-events --api-key YOUR_API_KEY

n8n

Start the server in HTTP mode:

npx @cryptoapis-io/mcp-blockchain-events --transport http --port 3000 --api-key YOUR_API_KEY

In your n8n workflow, add an AI Agent node
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

`blockchain_events_manage`

Manage existing webhook subscriptions.

Action	Description
`list-subscriptions`	List all webhook subscriptions
`get-subscription`	Get details of a specific subscription
`delete-subscription`	Delete a subscription
`activate-subscription`	Activate a paused subscription

`blockchain_events_create`

Create new webhook subscriptions for blockchain events.

Parameter	Description
`eventType`	Event type to subscribe to (e.g., new block, confirmed transaction, address coins)
`callbackUrl`	URL to receive webhook notifications
`blockchain`	Target blockchain (optional, depends on event type)
`network`	Target network (optional, depends on event type)
`address`	Address to monitor (optional, depends on event type)

CLI Arguments

Argument	Description	Default
`--api-key`	Crypto APIs API key	`CRYPTOAPIS_API_KEY` env var
`--transport`	Transport type: `stdio` or `http`	`stdio`
`--host`	HTTP host	`0.0.0.0`
`--port`	HTTP port	`3000`
`--path`	HTTP path	`/mcp`
`--stateless`	Enable stateless HTTP mode	`false`

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-blockchain-events --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.