get-balance

THE RISK

Low Risk

Why get-balance needs a policy

This tool retrieves balance information from a blockchain address, which is a read-only query operation with no side effects. It returns data without creating, modifying, or deleting anything. Even in the worst case where an AI agent misuses this tool, it can only enumerate or exfiltrate balance data, which has low impact.

From the tool's definition Tool name 'get-balance' and description 'Get an address' indicate retrieval of account balance information. The context describes a blockchain server where this tool would query blockchain data without modifying state.

Documented attack patterns abuse exactly the kind of access get-balance gives an agent:

POLICY

How to control get-balance

PolicyLayer is an MCP gateway — it sits between your AI agents and MCP Blockchain Server, and nothing reaches the server without passing your rules. This is the rule we recommend for get-balance:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "get-balance": {}
  }
}

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

Create a free account and register MCP Blockchain Server — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More MCP Blockchain Server tools

Write prepare-transaction Create an unsigned transaction and return a URL the user opens to review and sign it in Read get-chains List the blockchain networks this server supports, with their chain ids and native currenc Read get-transaction-status Check the current status of a prepared transaction by its id. Read read-contract Call a read-only (view/pure) contract method. Provide

All 5 MCP Blockchain Server tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about get-balance

What does the get-balance tool do? +

Get an address. It is categorised as a Read tool in the MCP Blockchain Server MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on get-balance? +

Register the MCP Blockchain Server MCP server in PolicyLayer and add a rule for get-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 MCP Blockchain Server. Nothing to install.

What risk level is get-balance? +

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

Can I rate-limit get-balance? +

Yes. Add a rate_limit block to the get-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 get-balance completely? +

Set action: deny in the PolicyLayer policy for get-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 get-balance? +

get-balance is provided by the MCP Blockchain Server MCP server (zhangzhongnan928/mcp-blockchain-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every MCP Blockchain Server tool call.

Start from MCP Blockchain Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →