update_catalog_variable · ServiceNow MCP Server MCP

WHAT IT DOES

What update_catalog_variable does on ServiceNow MCP Server

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

WHY IT NEEDS A POLICY

Why update_catalog_variable needs a policy

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

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_catalog_variable Rate-limited

update_catalog_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": {
    "update_catalog_variable": {
      "limits": [
        {
          "counter": "update_catalog_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 ServiceNow MCP Server, so you can run agents against it safely.

FAQ

Questions about update_catalog_variable

What does the update_catalog_variable tool do? +

Update fields on an existing catalog variable. It is categorised as a Write tool in the ServiceNow 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 update_catalog_variable? +

Register the ServiceNow MCP Server MCP server in PolicyLayer and add a rule for update_catalog_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 ServiceNow MCP Server. Nothing to install.

What risk level is update_catalog_variable? +

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

Can I rate-limit update_catalog_variable? +

Yes. Add a rate_limit block to the update_catalog_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 update_catalog_variable completely? +

Set action: deny in the PolicyLayer policy for update_catalog_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 update_catalog_variable? +

update_catalog_variable is provided by the ServiceNow MCP Server MCP server (windoze95/servicewow-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.