create_suppression_rule

Server Stepsecurity step-security/stepsecurity-mcp

Category Write

Risk class Medium

Parameters 00 required

WHAT IT DOES

What create_suppression_rule does on Stepsecurity

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

WHY IT NEEDS A POLICY

Why create_suppression_rule needs a policy

An AI agent can call create_suppression_rule faster than any human can review — one bad instruction and it creates or modifies resources in Stepsecurity by the hundred, each call as confident as the last.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_suppression_rule Rate-limited

create_suppression_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": {
    "create_suppression_rule": {
      "limits": [
        {
          "counter": "create_suppression_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 Stepsecurity, so you can run agents against it safely.

FAQ

Questions about create_suppression_rule

What does the create_suppression_rule tool do? +

Create a suppression rule. WRITE OPERATION — requires confirm: true and a read-only API key will 403. Before calling this, you MUST call preview_suppression_rule with the same conditions and show the user the expected impact. Creating a rule also retroactively suppresses matching past detections (synchronous server-side). After creation the tool verifies how many past detections were moved. Severity action is hardcoded to. It is categorised as a Write tool in the Stepsecurity MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create_suppression_rule? +

Register the Stepsecurity MCP server in PolicyLayer and add a rule for create_suppression_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 Stepsecurity. Nothing to install.

What risk level is create_suppression_rule? +

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

Can I rate-limit create_suppression_rule? +

Yes. Add a rate_limit block to the create_suppression_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 create_suppression_rule completely? +

Set action: deny in the PolicyLayer policy for create_suppression_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 create_suppression_rule? +

create_suppression_rule is provided by the Stepsecurity MCP server (step-security/stepsecurity-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.