detach_user_policy · Finch MCP Server MCP: Risk & Policy

WHAT IT DOES

What detach_user_policy does on Finch MCP Server

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

WHY IT NEEDS A POLICY

Why detach_user_policy needs a policy

The tool name 'detach_user_policy' strongly implies removing/detaching an IAM policy from a user, which is a reversible write operation (the policy can be re-attached). However, detaching a policy can remove access controls and has significant security implications. Confidence is reduced due to the empty description.

From the tool's definition Tool name: detach_user_policy — description is empty/uninformative

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

detach_user_policy Rate-limited

detach_user_policy 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": {
    "detach_user_policy": {
      "limits": [
        {
          "counter": "detach_user_policy_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 Finch MCP Server, so you can run agents against it safely.

FAQ

Questions about detach_user_policy

What does the detach_user_policy tool do? +

detach_user_policy. It is categorised as a Write tool in the Finch MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on detach_user_policy? +

Register the Finch MCP Server MCP server in PolicyLayer and add a rule for detach_user_policy: 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 Finch MCP Server. Nothing to install.

What risk level is detach_user_policy? +

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

Can I rate-limit detach_user_policy? +

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

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

detach_user_policy is provided by the Finch MCP Server MCP server (awslabs.finch-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.