run_to_event · Rr MCP: Risk & Policy

WHAT IT DOES

What run_to_event does on Rr

AI agents invoke run_to_event to trigger actions in Rr. 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 run_to_event needs a policy

This tool triggers execution of code/program operations whose effects depend on arguments (the event number specified). While not destructive or financial, it actively executes program state changes. Misuse could allow an agent to manipulate program execution, skip important breakpoints, or execute arbitrary code paths.

From the tool's definition Tool name 'run_to_event' and description 'Run to a specific event number' indicate active execution control.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

run_to_event Rate-limited

run_to_event 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": {
    "run_to_event": {
      "limits": [
        {
          "counter": "run_to_event_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 Rr, so you can run agents against it safely.

FAQ

Questions about run_to_event

What does the run_to_event tool do? +

Run to a specific event number (rr global time). It is categorised as a Execute tool in the Rr MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on run_to_event? +

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

What risk level is run_to_event? +

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

Can I rate-limit run_to_event? +

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

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

run_to_event is provided by the Rr MCP server (jnjaeschke/rr-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.