factorial · Calculator MCP: Risk & Policy

WHAT IT DOES

What factorial does on Calculator MCP

AI agents invoke factorial to trigger actions in Calculator 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 factorial needs a policy

Factorial calculation is a computational operation that executes a mathematical function. It has no data read/write side effects and is not destructive or financial. It falls under Execute as it runs a computation. Severity is low since it is a bounded arithmetic operation, though very large inputs could cause performance issues (e.g., factorial of a huge number).

From the tool's definition Tool name 'factorial' and description '计算整数阶乘' (calculate integer factorial) — performs a mathematical computation/calculation.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

factorial Rate-limited

factorial 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": {
    "factorial": {
      "limits": [
        {
          "counter": "factorial_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 Calculator MCP, so you can run agents against it safely.

FAQ

Questions about factorial

What does the factorial tool do? +

计算整数阶乘. It is categorised as a Execute tool in the Calculator 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 factorial? +

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

What risk level is factorial? +

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

Can I rate-limit factorial? +

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

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

factorial is provided by the Calculator MCP server (kelseyee/mcp_calculator). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.