vast42_update_companion · AdButler MCP: Risk & Policy

WHAT IT DOES

What vast42_update_companion does on AdButler

AI agents use vast42_update_companion to create or update resources in AdButler — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your AdButler environment.

PARAMETERS

Parameter	Type	Required	Description
`id`	number	Yes	VAST 4.2 companion ID
`name`	string	—	Companion name
`width`	number	—	Companion width in pixels
`height`	number	—	Companion height in pixels

Parameters from the server's own tool schema.

WHY IT NEEDS A POLICY

Why vast42_update_companion needs a policy

This tool modifies VAST (Video Ad Serving Template) companion ad configurations, which is a reversible write operation. It does not delete data (would be Destructive), execute arbitrary code (would be Execute), move money (would be Financial), or merely retrieve data (would be Read).

From the tool's definition Tool name contains 'update' and description states 'Update a VAST 4.2 companion', indicating modification of existing data (VAST companion ad configuration).

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

vast42_update_companion Rate-limited

vast42_update_companion 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": {
    "vast42_update_companion": {
      "limits": [
        {
          "counter": "vast42_update_companion_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 AdButler, so you can run agents against it safely.

FAQ

Questions about vast42_update_companion

What does the vast42_update_companion tool do? +

Update a VAST 4.2 companion. It is categorised as a Write tool in the AdButler MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

What parameters does vast42_update_companion accept? +

vast42_update_companion accepts 4 parameters: id, name, width, height. Required: id. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on vast42_update_companion? +

Register the AdButler MCP server in PolicyLayer and add a rule for vast42_update_companion: 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 AdButler. Nothing to install.

What risk level is vast42_update_companion? +

vast42_update_companion is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit vast42_update_companion? +

Yes. Add a rate_limit block to the vast42_update_companion 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 vast42_update_companion completely? +

Set action: deny in the PolicyLayer policy for vast42_update_companion. 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 vast42_update_companion? +

vast42_update_companion is provided by the AdButler MCP server (adbutler/mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.