stop_runtime_session · Awslabs Valkey MCP: Risk & Policy

WHAT IT DOES

What stop_runtime_session does on Awslabs Valkey

AI agents invoke stop_runtime_session to trigger actions in Awslabs Valkey. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why stop_runtime_session needs a policy

The tool performs an action that terminates or halts an active runtime session, which is an operational effect that depends on which session is targeted. While not strictly destructive (the session state may resume), it triggers external effects on ElastiCache/MemoryDB infrastructure. Without a description, confidence is moderate, but the name clearly indicates an Execute-class action.

From the tool's definition Tool name 'stop_runtime_session' indicates termination of an active session; no description provided to clarify scope, but stopping runtime sessions affects external system state and operation.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

stop_runtime_session Rate-limited

stop_runtime_session stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "stop_runtime_session": {
      "limits": [
        {
          "counter": "stop_runtime_session_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-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 stop_runtime_session

What does the stop_runtime_session tool do? +

stop_runtime_session. It is categorised as a Execute tool in the Awslabs Valkey MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on stop_runtime_session? +

Register the Awslabs Valkey MCP server in PolicyLayer and add a rule for stop_runtime_session: 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 stop_runtime_session? +

stop_runtime_session is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit stop_runtime_session? +

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

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

stop_runtime_session 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.