create_subnet · OCI MCP Server MCP: Risk & Policy

WHAT IT DOES

What create_subnet does on OCI MCP Server

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

WHY IT NEEDS A POLICY

Why create_subnet needs a policy

Creating a subnet is a Write operation—it creates new infrastructure resources that are reversible (the subnet can be deleted). However, severity is elevated to 'high' because subnets are critical network infrastructure whose creation can enable lateral movement, expose services, or alter network topology in ways that could compromise security posture.

From the tool's definition Tool name is 'create_subnet' and description states it creates a subnet, a foundational networking resource in OCI.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_subnet Rate-limited

create_subnet 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_subnet": {
      "limits": [
        {
          "counter": "create_subnet_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 OCI MCP Server, so you can run agents against it safely.

FAQ

Questions about create_subnet

What does the create_subnet tool do? +

Create a subnet. Omit availability_domain for a regional subnet. It is categorised as a Write tool in the OCI 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_subnet? +

Register the OCI MCP Server MCP server in PolicyLayer and add a rule for create_subnet: 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 OCI MCP Server. Nothing to install.

What risk level is create_subnet? +

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

Can I rate-limit create_subnet? +

Yes. Add a rate_limit block to the create_subnet 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_subnet completely? +

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

create_subnet is provided by the OCI MCP Server MCP server (sarthak-pansare/oci-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.