Flow

You run an MCP server that gives you access to Flow blockchain data and actions through a standardized interface. It lets you check balances, resolve domains, read data with scripts, submit and monitor transactions, and retrieve account information, all in a configurable, developer-friendly way.

How to use

You can run the Flow MCP Server in standard I/O mode to integrate with AI assistants, or run it as an HTTP server if you provide a destination URL. The server exposes tools to query balances, retrieve account data, resolve domains, execute Cadence scripts, and submit or inspect transactions. Start it in stdio mode for seamless integration with AI tool configurations, or run it in HTTP mode on a port you specify to expose a REST-like interface.

Practical usage patterns include: starting the server with the MCP runtime, then sending tool requests for balance lookups, domain resolutions, script executions, and transaction operations. You can switch between networks (mainnet, testnet, or emulator) by configuring the appropriate environment variables or startup options. When you want to run locally for development, build and start the server, then access it through the appropriate interface.

How to install

Prerequisites: you need Node.js and npm installed on your system. Verify your versions before proceeding.

Option A: Run with npx (recommended) in stdio mode for AI assistant integration.

npx -y @outblock/flow-mcp-server --stdio

Option A extended: run as an HTTP server on a specific port if you prefer a network interface.

npx -y @outblock/flow-mcp-server --port 3000

Option B: Local installation for development. Clone the repository, install dependencies, build, and start.

git clone https://github.com/lmcmz/flow-mcp-server.git
 cd flow-mcp-server
 npm install
 npm run build
 npm start

Option B extended: for development with automatic reloads, you can use a development command if provided.

npm run dev

Configuration and environment

Configure how you connect to Flow and how the MCP server behaves by setting environment variables. The following variables are commonly used to tailor network, endpoints, and logging to your needs.

• PORT: HTTP port to listen on (if not set, the server runs in stdio mode)

• FLOW_NETWORK: Flow network to connect to (mainnet, testnet, emulator)

• FLOW_ACCESS_NODE: Custom Flow access node URL

• LOG_LEVEL: Logging level (debug, info, warn, error)

These variables guide runtime behavior and can be overridden per deployment scenario.

Using with AI assistants

To integrate with AI assistants, launch the MCP server in stdio mode and connect it to your assistant’s tool configuration. This enables the assistant to perform balance checks, domain resolutions, script reads, and transaction operations against the Flow blockchain.

{
  "tools": [
    {
      "name": "flow-mcp-server",
      "command": "npx -y @outblock/flow-mcp-server --stdio"
    }
  ]
}

Notes on usage and security

Keep your Flow access tokens and private data secure. Use network-level access controls when exposing the HTTP interface and prefer stdio mode for local development and AI integrations. Regularly rotate any credentials used for access nodes and monitor logs for unusual activity.

If you need to switch networks or endpoints, adjust the FLOW_NETWORK and FLOW_ACCESS_NODE values accordingly and restart the server to apply changes.

Available tools and capabilities

The Flow MCP Server provides a set of actions that you can invoke through tool requests. These include getting the Flow balance, querying fungible token balances, retrieving account details, resolving .find and .fn domains, executing Cadence scripts, sending transactions, and obtaining transaction information.

Available tools

get_balance

Retrieve the Flow balance for a given address on the specified network.

get_token_balance

Retrieve the fungible token balance for a given address.

get_account

Fetch account information for a given Flow account address.

resolve_domain

Resolve a .find or .fn domain to its corresponding Flow address.

execute_script

Execute a Cadence script to read on-chain data.

send_transaction

Submit a transaction to the Flow blockchain.

get_transaction

Retrieve details for a specific transaction by its ID.