presonus-studiolive-mcp: Skill for Claude Code

MCP Write Safety Gate

Purpose

Use this skill for every write-capable MCP tool and every adapter method that changes mixer state.

A write-capable tool must be safe by default. It must not mutate mixer state unless writes are explicitly enabled, validated, preflighted, and verified.

Applies to

• channel mute writes
• channel fader writes
• aux send level writes
• aux send mute writes
• Fat Channel parameter writes
• preset application
• routing writes, if added later
• scene/state changes
• any adapter method that mutates mixer state

Hard rules

1. Default mode is read-only.
2. Writes require an explicit environment flag.
3. Writes require a dry-run path.
4. Writes require parameter validation.
5. Writes require preflight state read.
6. Writes require proposed-change summary.
7. Writes require post-write verification.
8. Writes require HIL evidence before being advertised as supported.
9. Risky writes require rollback or restore procedure.
10. Never execute writes in tests unless using a mock or an explicit HIL write test target.

Required environment gate

Use a single obvious flag:

PRESONUS_MCP_ENABLE_WRITES=true

If this flag is absent, all write tools must return dry-run or disabled responses.

Required response shape

Write tools must return a response equivalent to:

{
  "status": "dry_run",
  "writeEnabled": false,
  "dryRun": true,
  "tool": "set_channel_fader",
  "target": {
    "channel": 1
  },
  "before": {
    "faderDb": -12.0
  },
  "proposed": {
    "faderDb": -10.0
  },
  "validation": {
    "rangeValid": true,
    "targetExists": true,
    "hilStatus": "implemented_unverified"
  },
  "risk": "medium",
  "requiresConfirmation": true,
  "postWriteVerificationAvailable": true,
  "rollback": {
    "available": true,
    "restore": {
      "faderDb": -12.0
    }
  },
  "executed": false
}

For enabled writes:

{
  "status": "verified",
  "writeEnabled": true,
  "dryRun": false,
  "executed": true,
  "before": {},
  "requested": {},
  "after": {},
  "verification": {
    "matched": true,
    "tolerance": "..."
  }
}