cron_run · MCP Cron Server MCP: Risk & Policy

WHAT IT DOES

What cron_run does on MCP Cron Server

AI agents invoke cron_run to trigger actions in MCP Cron 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 cron_run needs a policy

This tool directly triggers execution of scheduled tasks. While the actual impact depends on what each cron job contains, the tool's purpose is to invoke external operations immediately.

From the tool's definition Tool description indicates '立即执行定时任务（不等待调度）' which translates to 'immediately execute scheduled task (without waiting for scheduling)'. The tool triggers execution of cron jobs on demand.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

cron_run Rate-limited

cron_run 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": {
    "cron_run": {
      "limits": [
        {
          "counter": "cron_run_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 MCP Cron Server, so you can run agents against it safely.

FAQ

Questions about cron_run

What does the cron_run tool do? +

立即执行定时任务（不等待调度）. It is categorised as a Execute tool in the MCP Cron 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 cron_run? +

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

What risk level is cron_run? +

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

Can I rate-limit cron_run? +

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

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

cron_run is provided by the MCP Cron Server MCP server (nolan57/opencode-mcp-cron). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.