deploy-contract · MCP EVM Signer MCP: Risk & Policy

WHAT IT DOES

What deploy-contract does on MCP EVM Signer

AI agents use deploy-contract to commit financial operations through MCP EVM Signer — usually the final step of a payment, billing, or trading workflow. A call moves real money.

WHY IT NEEDS A POLICY

Why deploy-contract needs a policy

Deploying a smart contract is an irreversible on-chain transaction that consumes ETH (gas fees) and permanently publishes code to the blockchain. It commits financial resources (gas) and can establish contracts that control funds, tokens, or other financial logic.

From the tool's definition 'Deploy a smart contract' on an EVM-compatible blockchain using locally managed Ethereum private keys

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

deploy-contract Approval-gated

Any call to deploy-contract is blocked until a human approves it. The rest of the server keeps working.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "deploy-contract": {
      "deny_if": [
        {
          "conditions": [],
          "on_deny": "Requires human approval."
        }
      ]
    }
  }
}

GATE THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches MCP EVM Signer, so you can run agents against it safely.

FAQ

Questions about deploy-contract

What does the deploy-contract tool do? +

Deploy a smart contract. It is categorised as a Financial tool in the MCP EVM Signer MCP Server, which means it involves financial transactions. Block by default and require explicit approval.

How do I enforce a policy on deploy-contract? +

Register the MCP EVM Signer MCP server in PolicyLayer and add a rule for deploy-contract: 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 EVM Signer. Nothing to install.

What risk level is deploy-contract? +

deploy-contract is a Financial tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.

Can I rate-limit deploy-contract? +

Yes. Add a rate_limit block to the deploy-contract 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 deploy-contract completely? +

Set action: deny in the PolicyLayer policy for deploy-contract. 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 deploy-contract? +

deploy-contract is provided by the MCP EVM Signer MCP server (zhangzhongnan928/mcp-evm-signer). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.