reminders · Apple MCP: Risk & Policy

WHAT IT DOES

What reminders does on Apple MCP

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

WHY IT NEEDS A POLICY

Why reminders needs a policy

Creating reminders is a reversible write operation that modifies the user's data in the Reminders app. It does not delete data (ruling out Destructive), execute arbitrary code (ruling out Execute), or involve financial transactions.

From the tool's definition Tool allows 'create' and 'open reminders' - these are write operations that modify state in the Apple Reminders app. The 'search' aspect is read-only, but the create capability dominates the classification.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

reminders Rate-limited

reminders 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": {
    "reminders": {
      "limits": [
        {
          "counter": "reminders_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 Apple MCP, so you can run agents against it safely.

FAQ

Questions about reminders

What does the reminders tool do? +

Search, create, and open reminders in Apple Reminders app. It is categorised as a Write tool in the Apple MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on reminders? +

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

What risk level is reminders? +

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

Can I rate-limit reminders? +

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

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

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