schedule_function_call · Simple MCP: Risk & Policy

WHAT IT DOES

What schedule_function_call does on Simple MCP

AI agents invoke schedule_function_call to trigger actions in Simple MCP. 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 schedule_function_call needs a policy

The tool name strongly suggests it schedules function calls for future execution, which falls under the Execute category. The server description explicitly mentions 'job scheduling' capabilities. While the description is empty (lowering confidence), sibling tools like 'cancel_scheduled_job' and 'get_job_execution_log' confirm this is part of a job scheduling system.

From the tool's definition Tool name 'schedule_function_call' implies scheduling execution of arbitrary functions; server description mentions 'job scheduling' as a core capability

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

schedule_function_call Rate-limited

schedule_function_call 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": {
    "schedule_function_call": {
      "limits": [
        {
          "counter": "schedule_function_call_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

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PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Simple MCP, so you can run agents against it safely.

FAQ

Questions about schedule_function_call

What does the schedule_function_call tool do? +

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

How do I enforce a policy on schedule_function_call? +

Register the Simple MCP server in PolicyLayer and add a rule for schedule_function_call: 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 Simple MCP. Nothing to install.

What risk level is schedule_function_call? +

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

Can I rate-limit schedule_function_call? +

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

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

schedule_function_call is provided by the Simple MCP server (karar-hayder/simple-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.