update_rules · Starlog MCP: Risk & Policy

WHAT IT DOES

What update_rules does on Starlog

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

WHY IT NEEDS A POLICY

Why update_rules needs a policy

This tool modifies project rules by replacing them entirely. While the change is theoretically reversible (a previous state could be restored or rules re-edited), it modifies stored configuration data that other workflows depend on.

From the tool's definition Tool description states it will 'Replace all project rules', which is a modification operation. The verb 'Replace' and 'update' in the tool name indicate reversible data mutation.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_rules Rate-limited

update_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": {
    "update_rules": {
      "limits": [
        {
          "counter": "update_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 Starlog, so you can run agents against it safely.

FAQ

Questions about update_rules

What does the update_rules tool do? +

Replace all project rules with RulesEntry models. It is categorised as a Write tool in the Starlog 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_rules? +

Register the Starlog MCP server in PolicyLayer and add a rule for update_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 Starlog. Nothing to install.

What risk level is update_rules? +

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

Can I rate-limit update_rules? +

Yes. Add a rate_limit block to the update_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 update_rules completely? +

Set action: deny in the PolicyLayer policy for update_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 update_rules? +

update_rules is provided by the Starlog MCP server (sancovp/starlog-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.