put_user_policy · Awslabs Valkey MCP: Risk & Policy

WHAT IT DOES

What put_user_policy does on Awslabs Valkey

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

WHY IT NEEDS A POLICY

Why put_user_policy needs a policy

The tool modifies AWS IAM user policies, which controls access permissions. While reversible (policies can be updated or deleted), this is a Write operation with high severity due to the security implications of modifying user permissions. The empty description lowers confidence slightly, but the naming convention is clear enough for AWS tools.

From the tool's definition Tool name 'put_user_policy' indicates creation or modification of an IAM user policy. The 'put' prefix combined with 'policy' in an AWS context typically creates or overwrites a policy document, which is a reversible write operation.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

put_user_policy Rate-limited

put_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": {
    "put_user_policy": {
      "limits": [
        {
          "counter": "put_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 Awslabs Valkey, so you can run agents against it safely.

FAQ

Questions about put_user_policy

What does the put_user_policy tool do? +

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

How do I enforce a policy on put_user_policy? +

Register the Awslabs Valkey MCP server in PolicyLayer and add a rule for put_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 Awslabs Valkey. Nothing to install.

What risk level is put_user_policy? +

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

Can I rate-limit put_user_policy? +

Yes. Add a rate_limit block to the put_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 put_user_policy completely? +

Set action: deny in the PolicyLayer policy for put_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 put_user_policy? +

put_user_policy is provided by the Awslabs Valkey MCP server (awslabs.valkey-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.