createWebhookSubscription · Hevy MCP Server MCP

WHAT IT DOES

What createWebhookSubscription does on Hevy MCP Server

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

WHY IT NEEDS A POLICY

Why createWebhookSubscription needs a policy

This tool creates a new webhook subscription, which modifies platform state by establishing a new callback configuration. This is reversible (subscriptions can be deleted via deleteWebhookSubscription), so it falls under Write rather than Destructive.

From the tool's definition Tool name 'createWebhookSubscription' and description 'Create a new webhook subscription' indicate data creation that adds a new webhook endpoint configuration to the Hevy platform.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

createWebhookSubscription Rate-limited

createWebhookSubscription 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": {
    "createWebhookSubscription": {
      "limits": [
        {
          "counter": "createwebhooksubscription_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 Hevy MCP Server, so you can run agents against it safely.

FAQ

Questions about createWebhookSubscription

What does the createWebhookSubscription tool do? +

Create a new webhook subscription. It is categorised as a Write tool in the Hevy 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 createWebhookSubscription? +

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

What risk level is createWebhookSubscription? +

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

Can I rate-limit createWebhookSubscription? +

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

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

createWebhookSubscription is provided by the Hevy MCP Server MCP server (jcjiron/hevy-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.