quantize_notes · Orpheus MCP: Risk & Policy

WHAT IT DOES

What quantize_notes does on Orpheus

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

WHY IT NEEDS A POLICY

Why quantize_notes needs a policy

Quantization adjusts note start times and durations to align with a metrical grid, which changes the musical content of the take. This is a modification (Write) rather than deletion—the original notes are still present, just repositioned. It is not Execute because it does not run arbitrary code or trigger conditional side effects; it applies a deterministic, parameterized transformation.

From the tool's definition "Quantize a take's notes to a grid" – this modifies MIDI note timing by snapping notes to rhythmic grid positions. This is a reversible alteration of project data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

quantize_notes Rate-limited

quantize_notes 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": {
    "quantize_notes": {
      "limits": [
        {
          "counter": "quantize_notes_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 Orpheus, so you can run agents against it safely.

FAQ

Questions about quantize_notes

What does the quantize_notes tool do? +

Quantize a take's notes to a grid (cleanup before/after analysis). It is categorised as a Write tool in the Orpheus MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on quantize_notes? +

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

What risk level is quantize_notes? +

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

Can I rate-limit quantize_notes? +

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

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

quantize_notes is provided by the Orpheus MCP server (mal0ware/orpheus). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.