Low Risk

binance_us_cust_balance

Get balance information for Binance.US exchange wallet and custodial sub-account. ⚠️ REQUIRES CUSTODIAL SOLUTION API KEY - Standard API keys will not work. This endpoint is for institutional custody partners (e.g., Anchorage, BitGo). Response includes: - exchangeWalletBalance: Balances in your Bi...

How to control binance_us_cust_balance ↓

AI agents call binance_us_cust_balance to retrieve information from BNB Chain MCP without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

Low Risk

This tool only retrieves balance information (asset, free, locked balances) from Binance.US and custodial sub-accounts. It performs no writes, transfers, or financial operations. Severity is medium because it exposes sensitive financial account balance data including custodial institutional account details, which could aid reconnaissance for attacks.

From the tool's definition Get balance information for Binance.US exchange wallet and custodial sub-account

Documented attack patterns abuse exactly the kind of access binance_us_cust_balance gives an agent:

PolicyLayer is an MCP gateway — it sits between your AI agents and BNB Chain MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for binance_us_cust_balance:

policy.json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "binance_us_cust_balance": {}
  }
}

binance_us_cust_balance is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

  1. Create a free account and register BNB Chain MCP — nothing to install.
  2. Add this policy — paste it, or build it visually.
  3. Point your MCP client (Claude, Cursor, anything) at your gateway URL.
CAP THIS TOOL →

Free to start. No card required.

Go deeper

What does the binance_us_cust_balance tool do? +

Get balance information for Binance.US exchange wallet and custodial sub-account. ⚠️ REQUIRES CUSTODIAL SOLUTION API KEY - Standard API keys will not work. This endpoint is for institutional custody partners (e.g., Anchorage, BitGo). Response includes: - exchangeWalletBalance: Balances in your Binance.US exchange wallet - custodialAcctBalance: Balances in your custodial sub-account Each balance entry contains: - asset: Asset symbol - free: Available balance - locked: Locked balance - inSettlement: Amount in settlement (custodial only) - lastUpdatedTime: Last update timestamp. It is categorised as a Read tool in the BNB Chain MCP MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on binance_us_cust_balance? +

Register the BNB Chain MCP server in PolicyLayer and add a rule for binance_us_cust_balance: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches BNB Chain MCP. Nothing to install.

What risk level is binance_us_cust_balance? +

binance_us_cust_balance is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit binance_us_cust_balance? +

Yes. Add a rate_limit block to the binance_us_cust_balance rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block binance_us_cust_balance completely? +

Set action: deny in the PolicyLayer policy for binance_us_cust_balance. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides binance_us_cust_balance? +

binance_us_cust_balance is provided by the BNB Chain MCP server (nirholas/bnbchain-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every BNB Chain MCP tool call.

Deterministic rules across all 1240 BNB Chain MCP tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.

Free to start. No card required.

1240 BNB Chain MCP tools catalogued and risk-classified — across an index of 42,500+ MCP servers.

// GET IN TOUCH

Have a question or want to learn more? Send us a message.

Message sent.

We'll get back to you soon.