roll_disadvantage · Dice Roller MCP Server MCP

WHAT IT DOES

What roll_disadvantage does on Dice Roller MCP Server

AI agents invoke roll_disadvantage to trigger actions in Dice Roller 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 roll_disadvantage needs a policy

This tool executes a randomized dice-rolling operation (rolling twice and selecting the lower result), which is a computation/execution action rather than a simple data read or write. It produces non-deterministic output by running a random number generation process. The blast radius is minimal as it only affects tabletop game mechanics with no real-world consequences.

From the tool's definition 'Roll with disadvantage (roll twice, take the lower result)' — triggers an external dice-rolling operation with computed results

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

roll_disadvantage Rate-limited

roll_disadvantage 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": {
    "roll_disadvantage": {
      "limits": [
        {
          "counter": "roll_disadvantage_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 Dice Roller MCP Server, so you can run agents against it safely.

FAQ

Questions about roll_disadvantage

What does the roll_disadvantage tool do? +

Roll with disadvantage (roll twice, take the lower result) for DnD 5e. It is categorised as a Execute tool in the Dice Roller 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 roll_disadvantage? +

Register the Dice Roller MCP Server MCP server in PolicyLayer and add a rule for roll_disadvantage: 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 Dice Roller MCP Server. Nothing to install.

What risk level is roll_disadvantage? +

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

Can I rate-limit roll_disadvantage? +

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

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

roll_disadvantage is provided by the Dice Roller MCP Server MCP server (swayam-mishra/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.