create-variable · Terrakube MCP Server MCP: Risk & Policy

WHAT IT DOES

What create-variable does on Terrakube MCP Server

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

WHY IT NEEDS A POLICY

Why create-variable needs a policy

Creating variables in a Terrakube workspace is a reversible write operation—variables can be edited or deleted later. It does not destroy data (Destructive), execute arbitrary code (Execute), involve financial transactions (Financial), or merely read data (Read).

From the tool's definition Tool name is 'create-variable' and description states it 'Creates a new variable in the specified workspace'. This is clearly a creation operation that modifies state by adding a new variable.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create-variable Rate-limited

create-variable 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-variable": {
      "limits": [
        {
          "counter": "create-variable_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 Terrakube MCP Server, so you can run agents against it safely.

FAQ

Questions about create-variable

What does the create-variable tool do? +

Creates a new variable in the specified workspace. It is categorised as a Write tool in the Terrakube MCP Server 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-variable? +

Register the Terrakube MCP Server MCP server in PolicyLayer and add a rule for create-variable: 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 Terrakube MCP Server. Nothing to install.

What risk level is create-variable? +

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

Can I rate-limit create-variable? +

Yes. Add a rate_limit block to the create-variable 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-variable completely? +

Set action: deny in the PolicyLayer policy for create-variable. 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-variable? +

create-variable is provided by the Terrakube MCP Server MCP server (terrakube-io/mcp-server-terrakube). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.