string_get_set · Amazon MQ MCP Server MCP: Risk & Policy

WHAT IT DOES

What string_get_set does on Amazon MQ MCP Server

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

WHY IT NEEDS A POLICY

Why string_get_set needs a policy

The tool writes/modifies a value (sets a new value) and returns the previous value. This is a reversible write operation. Confidence is moderate because the description is vague and doesn't specify what kind of data is being set, but the core action is a mutation/update which falls under Write.

From the tool's definition Set new value and return old value

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

string_get_set Rate-limited

string_get_set 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": {
    "string_get_set": {
      "limits": [
        {
          "counter": "string_get_set_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 Amazon MQ MCP Server, so you can run agents against it safely.

FAQ

Questions about string_get_set

What does the string_get_set tool do? +

Set new value and return old value. It is categorised as a Write tool in the Amazon MQ 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 string_get_set? +

Register the Amazon MQ MCP Server MCP server in PolicyLayer and add a rule for string_get_set: 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 Amazon MQ MCP Server. Nothing to install.

What risk level is string_get_set? +

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

Can I rate-limit string_get_set? +

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

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

string_get_set is provided by the Amazon MQ MCP Server MCP server (awslabs.amazon-mq-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.