create_stack · Sceptre MCP: Risk & Policy

WHAT IT DOES

What create_stack does on Sceptre

AI agents invoke create_stack to trigger actions in Sceptre. 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 create_stack needs a policy

Creating a CloudFormation stack provisions real cloud infrastructure and resources (compute, storage, networking, IAM, etc.), triggering external operations with significant blast radius. While it is not purely destructive or financial on its own, it executes an external infrastructure deployment that can incur costs and create persistent resources, making Execute the most appropriate category.

From the tool's definition Create a CloudFormation stack via Sceptre

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_stack Rate-limited

create_stack 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": {
    "create_stack": {
      "limits": [
        {
          "counter": "create_stack_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 Sceptre, so you can run agents against it safely.

FAQ

Questions about create_stack

What does the create_stack tool do? +

Create a CloudFormation stack via Sceptre. It is categorised as a Execute tool in the Sceptre MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on create_stack? +

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

What risk level is create_stack? +

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

Can I rate-limit create_stack? +

Yes. Add a rate_limit block to the create_stack 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_stack completely? +

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

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