stop_timer · Clockify MCP Server MCP: Risk & Policy

WHAT IT DOES

What stop_timer does on Clockify MCP Server

AI agents invoke stop_timer to trigger actions in Clockify MCP Server. 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_timer needs a policy

While the tool doesn't permanently destroy data or create financial transactions, it executes a command that changes system state—stopping an active timer. This falls under Execute rather than Write because it triggers a specific external operation rather than creating or modifying persistent data records directly.

From the tool's definition The tool description states it will 'Stop the currently running timer for the current user.' This is an action that modifies runtime state (a timer's active status), triggering an external operation with concrete side effects on the Clockify system.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

stop_timer Rate-limited

stop_timer 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_timer": {
      "limits": [
        {
          "counter": "stop_timer_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 Clockify MCP Server, so you can run agents against it safely.

FAQ

Questions about stop_timer

What does the stop_timer tool do? +

Stop the currently running timer for the current user. It is categorised as a Execute tool in the Clockify MCP Server 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_timer? +

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

What risk level is stop_timer? +

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

Can I rate-limit stop_timer? +

Yes. Add a rate_limit block to the stop_timer 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_timer completely? +

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

stop_timer is provided by the Clockify MCP Server MCP server (keithhanson/clockify-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.