update_weight · Whoop MCP Server MCP: Risk & Policy

WHAT IT DOES

What update_weight does on Whoop MCP Server

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

WHY IT NEEDS A POLICY

Why update_weight needs a policy

This tool creates or modifies health data (body weight) in the Whoop system. It is reversible and does not delete data, execute external commands, trigger financial transactions, or cause irreversible changes. It is therefore classified as Write. Severity is low because misuse (e.g., setting an incorrect weight) would only affect personal health tracking data without broader system or safety impact.

From the tool's definition Tool name 'update_weight' and description 'Update body weight on Whoop' indicates modification of user data. The operation is reversible (weight can be updated again with a different value) and has no external financial or destructive consequences.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_weight Rate-limited

update_weight 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_weight": {
      "limits": [
        {
          "counter": "update_weight_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 Whoop MCP Server, so you can run agents against it safely.

FAQ

Questions about update_weight

What does the update_weight tool do? +

Update body weight on Whoop. Accepts pounds, converts to kg automatically. It is categorised as a Write tool in the Whoop 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_weight? +

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

What risk level is update_weight? +

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

Can I rate-limit update_weight? +

Yes. Add a rate_limit block to the update_weight 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_weight completely? +

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

update_weight is provided by the Whoop MCP Server MCP server (jd1207/whoop-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.