transpose · Filopastry MCP: Risk & Policy

WHAT IT DOES

What transpose does on Filopastry

AI agents use transpose 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 transpose needs a policy

Transposing notes modifies musical pattern data by shifting pitch values. This is a reversible data modification (Write) within the music composition environment. It does not execute code, delete data, or have financial implications. Misuse has minimal blast radius as it only affects musical patterns within the Strudel environment.

From the tool's definition Transpose notes by semitones

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

transpose Rate-limited

transpose 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": {
    "transpose": {
      "limits": [
        {
          "counter": "transpose_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 transpose

What does the transpose tool do? +

Transpose notes by semitones. 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 transpose? +

Register the Filopastry MCP server in PolicyLayer and add a rule for transpose: 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 transpose? +

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

Can I rate-limit transpose? +

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

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

transpose 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.