approve_yei_token · SEI MCP Server V2 MCP: Risk & Policy

WHAT IT DOES

What approve_yei_token does on SEI MCP Server V2

AI agents use approve_yei_token to create or update resources in SEI MCP Server V2 — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your SEI MCP Server V2 environment.

WHY IT NEEDS A POLICY

Why approve_yei_token needs a policy

This tool creates or modifies blockchain state (ERC20 token allowance) reversibly. It is not destructive since allowances can be modified or revoked. It is not financial in the strict sense of moving funds, though it is a prerequisite for financial operations.

From the tool's definition Tool description explicitly states 'Approve the Yei Finance Pool contract to spend a specified amount of an ERC20 token' — this is a write operation that modifies the token allowance state on-chain.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

approve_yei_token Rate-limited

approve_yei_token stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "approve_yei_token": {
      "limits": [
        {
          "counter": "approve_yei_token_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches SEI MCP Server V2, so you can run agents against it safely.

FAQ

Questions about approve_yei_token

What does the approve_yei_token tool do? +

Approve the Yei Finance Pool contract to spend a specified amount of an ERC20 token. This is required before supplying or repaying. It is categorised as a Write tool in the SEI MCP Server V2 MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on approve_yei_token? +

Register the SEI MCP Server V2 MCP server in PolicyLayer and add a rule for approve_yei_token: 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 SEI MCP Server V2. Nothing to install.

What risk level is approve_yei_token? +

approve_yei_token is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit approve_yei_token? +

Yes. Add a rate_limit block to the approve_yei_token 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 approve_yei_token completely? +

Set action: deny in the PolicyLayer policy for approve_yei_token. 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 approve_yei_token? +

approve_yei_token is provided by the SEI MCP Server V2 MCP server (testinguser1111111/sei-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.