shopping_list · Personal Brain MCP: Risk & Policy

WHAT IT DOES

What shopping_list does on Personal Brain

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

WHY IT NEEDS A POLICY

Why shopping_list needs a policy

The tool explicitly supports both reading and modifying a shopping list. Since it can alter data (add/remove items), it falls under Write. The blast radius is medium — misuse could corrupt personal shopping data, but effects are reversible and limited in scope.

From the tool's definition 'View or modify your household shopping list' — the modify capability makes this a Write tool

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

shopping_list Rate-limited

shopping_list 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": {
    "shopping_list": {
      "limits": [
        {
          "counter": "shopping_list_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 Personal Brain, so you can run agents against it safely.

FAQ

Questions about shopping_list

What does the shopping_list tool do? +

View or modify your household shopping list. action=. It is categorised as a Write tool in the Personal Brain MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on shopping_list? +

Register the Personal Brain MCP server in PolicyLayer and add a rule for shopping_list: 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 Personal Brain. Nothing to install.

What risk level is shopping_list? +

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

Can I rate-limit shopping_list? +

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

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

shopping_list is provided by the Personal Brain MCP server (phantomts/personal-brain-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.