define_ontology · SensorMCP Server MCP: Risk & Policy

WHAT IT DOES

What define_ontology does on SensorMCP Server

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

WHY IT NEEDS A POLICY

Why define_ontology needs a policy

The tool creates or defines an ontology structure, which is data modification (Write category). However, with an empty description, confidence is moderate. In the SensorMCP context, ontology definition likely structures how objects are classified for detection models, making it a foundational Write operation rather than Execute or Destructive.

From the tool's definition Tool name 'define_ontology' combined with server context showing dataset creation and model training workflows.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

define_ontology Rate-limited

define_ontology 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": {
    "define_ontology": {
      "limits": [
        {
          "counter": "define_ontology_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 SensorMCP Server, so you can run agents against it safely.

FAQ

Questions about define_ontology

What does the define_ontology tool do? +

define_ontology. It is categorised as a Write tool in the SensorMCP 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 define_ontology? +

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

What risk level is define_ontology? +

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

Can I rate-limit define_ontology? +

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

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

define_ontology is provided by the SensorMCP Server MCP server (sensormcp/sensor-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.