bnbchain-mcp

BNB Chain MCP Skill

How to connect to the BNB Chain MCP server and use its tools: blocks, transactions, contracts, tokens, NFTs, wallet, ERC-8004 agents, and Greenfield. Use this skill when working with BNB Chain / opBNB / EVM or Greenfield via MCP.

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Connection and credentials

• Run the server: npx @bnb-chain/mcp@latest (fetches from npm at runtime). Source: github.com/bnb-chain/bnbchain-mcp.
• RPC: Default chains use built-in RPC; no config unless self-hosting or custom RPC.
• PRIVATE_KEY: Omit or leave empty for read-only (blocks, balances, contract reads). Set in the MCP server env for state-changing tools (transfers, write_contract, approve_token_spending, ERC-8004 register/set_uri, Greenfield writes). Never log or expose private keys.
• Read-only vs state-changing: Block/balance/contract-read tools work without a key; transfers and writes require PRIVATE_KEY in the server environment.

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1. MCP server config

Add the bnbchain-mcp server to the MCP client config (e.g. Cursor MCP settings, Claude Desktop claude_desktop_config.json).

Default (stdio):

{
  "mcpServers": {
    "bnbchain-mcp": {
      "command": "npx",
      "args": ["-y", "@bnb-chain/mcp@latest"],
      "env": {
        "PRIVATE_KEY": ""
      }
    }
  }
}

SSE mode: "args": ["-y", "@bnb-chain/mcp@latest", "--sse"] (and client SSE URL if required). Local dev server (e.g. bun dev:sse in bnbchain-mcp): "url": "http://localhost:3001/sse" with the same env.

Restart or reload the MCP client after changing config so the server starts.

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2. Credentials and environment

• RPC: Built-in for default chains.
• PRIVATE_KEY: Set in the server’s env when state-changing tools are needed; leave empty for read-only. Do not commit or echo keys.

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3. Agent registration (ERC-8004)

1. Register the agent on-chain with the MCP tool register_erc8004_agent (see references/erc8004-tools-reference.md).
2. Owners can then check registration on 8004scan (mainnet) or 8004scan (testnet).