update_webhook_subscription · Smokeball MCP: Risk & Policy

WHAT IT DOES

What update_webhook_subscription does on Smokeball

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

WHY IT NEEDS A POLICY

Why update_webhook_subscription needs a policy

This tool modifies webhook configuration settings (URL and active state) but does not delete data or execute arbitrary code. It represents reversible changes to notification infrastructure settings.

From the tool's definition Tool description explicitly states it 'Update[s] a webhook subscription URL or active state', indicating modification of existing configuration data. The 'active' parameter controls whether webhooks are enabled or disabled.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_webhook_subscription Rate-limited

update_webhook_subscription 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_webhook_subscription": {
      "limits": [
        {
          "counter": "update_webhook_subscription_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 Smokeball, so you can run agents against it safely.

FAQ

Questions about update_webhook_subscription

What does the update_webhook_subscription tool do? +

Update a webhook subscription URL or active state. active: 'true' or 'false'. It is categorised as a Write tool in the Smokeball 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_webhook_subscription? +

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

What risk level is update_webhook_subscription? +

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

Can I rate-limit update_webhook_subscription? +

Yes. Add a rate_limit block to the update_webhook_subscription 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_webhook_subscription completely? +

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

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