manage_rules · Bookie MCP: Risk & Policy

WHAT IT DOES

What manage_rules does on Bookie

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

WHY IT NEEDS A POLICY

Why manage_rules needs a policy

The tool's primary operations are Create and Delete on auto-categorization rules. While Delete could suggest Destructive category, these rules are configuration metadata rather than financial records themselves—they configure how transactions are categorized. Deleting a rule is reversible (rules can be recreated).

From the tool's definition Tool performs 'Create, list, delete, test, or get suggestions for auto-categorization rules.' Creating and deleting rules are write/destructive operations on configuration data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

manage_rules Rate-limited

manage_rules 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": {
    "manage_rules": {
      "limits": [
        {
          "counter": "manage_rules_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 Bookie, so you can run agents against it safely.

FAQ

Questions about manage_rules

What does the manage_rules tool do? +

Create, list, delete, test, or get suggestions for auto-categorization rules. A rule matches a case-insensitive substring of a transaction. It is categorised as a Write tool in the Bookie MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on manage_rules? +

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

What risk level is manage_rules? +

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

Can I rate-limit manage_rules? +

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

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

manage_rules is provided by the Bookie MCP server (yuens1002/bookie). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.