apply_master_match · Orpheus MCP: Risk & Policy

WHAT IT DOES

What apply_master_match does on Orpheus

AI agents invoke apply_master_match to trigger actions in Orpheus. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why apply_master_match needs a policy

The tool renders the master track and applies Matchering spectral analysis/processing against a reference fingerprint. This is an Execute-category action: it triggers an external rendering pipeline and applies irreversible-ish audio transformations.

From the tool's definition 'render the master → Matchering against the fingerprint's' — this tool renders the master output and applies Matchering (spectral/loudness matching processing), triggering an external audio rendering and processing operation

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

apply_master_match Rate-limited

apply_master_match stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "apply_master_match": {
      "limits": [
        {
          "counter": "apply_master_match_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-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 apply_master_match

What does the apply_master_match tool do? +

The spectral half: render the master → Matchering against the fingerprint's. It is categorised as a Execute tool in the Orpheus MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on apply_master_match? +

Register the Orpheus MCP server in PolicyLayer and add a rule for apply_master_match: 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 apply_master_match? +

apply_master_match is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit apply_master_match? +

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

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

apply_master_match 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.