draft_rule · Wrg Sigma Rules MCP: Risk & Policy

WHAT IT DOES

What draft_rule does on Wrg Sigma Rules

AI agents use draft_rule to create or update resources in Wrg Sigma Rules — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Wrg Sigma Rules environment.

WHY IT NEEDS A POLICY

Why draft_rule needs a policy

This tool creates or composes detection rules, which is a reversible write operation. The empty description reduces confidence slightly, but the name and server context make the intent clear. Severity is medium because malformed or adversarial rules could degrade security monitoring, but the effect is not destructive (rules can be edited/deleted) nor immediately dangerous like code execution.

From the tool's definition Tool name 'draft_rule' and server context indicate creation of new Sigma detection rules. Server description mentions 'writing, validation, and multi-backend conversion' of rules.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

draft_rule Rate-limited

draft_rule stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "draft_rule": {
      "limits": [
        {
          "counter": "draft_rule_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about draft_rule

What does the draft_rule tool do? +

draft_rule. It is categorised as a Write tool in the Wrg Sigma Rules MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on draft_rule? +

Register the Wrg Sigma Rules MCP server in PolicyLayer and add a rule for draft_rule: 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 Wrg Sigma Rules. Nothing to install.

What risk level is draft_rule? +

draft_rule is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit draft_rule? +

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

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

draft_rule is provided by the Wrg Sigma Rules MCP server (wrg-11/wrg-sigma-rules). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.