intervals_update_activity · Fitness MCP: Risk & Policy

WHAT IT DOES

What intervals_update_activity does on FitnessMCP

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

WHY IT NEEDS A POLICY

Why intervals_update_activity needs a policy

The tool appears to update existing activity data (workouts, training sessions, or performance metrics) in Intervals.icu, which is a Write operation—it modifies user data but does not permanently delete it or execute arbitrary code.

From the tool's definition Tool name 'intervals_update_activity' indicates modification of activity records in the Intervals.icu fitness service. The 'update' verb and context of a fitness data management server suggest this creates or modifies data reversibly within user fitness logs.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

intervals_update_activity Rate-limited

intervals_update_activity 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": {
    "intervals_update_activity": {
      "limits": [
        {
          "counter": "intervals_update_activity_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 FitnessMCP, so you can run agents against it safely.

FAQ

Questions about intervals_update_activity

What does the intervals_update_activity tool do? +

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

How do I enforce a policy on intervals_update_activity? +

Register the Fitness MCP server in PolicyLayer and add a rule for intervals_update_activity: 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 FitnessMCP. Nothing to install.

What risk level is intervals_update_activity? +

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

Can I rate-limit intervals_update_activity? +

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

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

intervals_update_activity is provided by the Fitness MCP server (senoj100-alt/fitnessmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.