Mute or unmute a media item.
AI agents use set_item_mute to create or update resources in Reaper — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Reaper environment.
This tool modifies the mute state of a media item, which is a reversible state change (toggling mute on/off). It does not execute arbitrary code, delete data irreversibly, or cause financial impact. The blast radius is limited to audio playback state within a single project, making this a Write-category tool with low severity.
From the tool's definition Tool name 'set_item_mute' and description 'Mute or unmute a media item' indicate state modification of a media item in REAPER DAW.
Documented attack patterns abuse exactly the kind of access set_item_mute gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Reaper, and nothing reaches the server without passing your rules. This is the rule we recommend for set_item_mute:
{
"version": "1",
"default": "deny",
"tools": {
"set_item_mute": {
"limits": [
{
"counter": "set_item_mute_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}set_item_mute 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.
Free to start. No card required.
Mute or unmute a media item. It is categorised as a Write tool in the Reaper MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Reaper MCP server in PolicyLayer and add a rule for set_item_mute: 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 Reaper. Nothing to install.
set_item_mute is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the set_item_mute 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.
Set action: deny in the PolicyLayer policy for set_item_mute. 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.
set_item_mute is provided by the Reaper MCP server (twelvetake-studios/reaper-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Reaper, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
158 Reaper tools catalogued and risk-classified — across an index of 43,000+ MCP servers.