reverse · Filopastry MCP: Risk & Policy

WHAT IT DOES

What reverse does on Filopastry

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

WHY IT NEEDS A POLICY

Why reverse needs a policy

The tool modifies music pattern data by reordering its elements (reversing sequence). This is a reversible transformation of existing data in memory/session, characteristic of Write operations. It does not delete, execute arbitrary commands, or cause financial impact. The blast radius is limited to the current music composition session.

From the tool's definition Tool name 'reverse' with description 'Reverse pattern' indicates a pattern manipulation operation. In the context of Strudel.cc live coding (a music generation platform), reversing a pattern modifies the sequence of notes/sounds in a reversible way, without…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

reverse Rate-limited

reverse 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": {
    "reverse": {
      "limits": [
        {
          "counter": "reverse_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 Filopastry, so you can run agents against it safely.

FAQ

Questions about reverse

What does the reverse tool do? +

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

How do I enforce a policy on reverse? +

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

What risk level is reverse? +

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

Can I rate-limit reverse? +

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

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

reverse is provided by the Filopastry MCP server (youwenshao/filopastry). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.