Set the master track volume.
AI agents use set_master_volume to create or update resources in Ableton — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Ableton environment.
This tool creates or modifies session data (the master volume setting) without deleting or destroying anything. The change is fully reversible by setting the volume to a different level. It's categorized as Write rather than Execute because it's a direct parameter modification, not a command execution.
From the tool's definition set_master_volume directly modifies the master track volume parameter in Ableton Live, a reversible change to session state.
Documented attack patterns abuse exactly the kind of access set_master_volume gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Ableton, and nothing reaches the server without passing your rules. This is the rule we recommend for set_master_volume:
{
"version": "1",
"default": "deny",
"tools": {
"set_master_volume": {
"limits": [
{
"counter": "set_master_volume_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}set_master_volume 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.
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Set the master track volume. It is categorised as a Write tool in the Ableton MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Ableton MCP server in PolicyLayer and add a rule for set_master_volume: 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 Ableton. Nothing to install.
set_master_volume 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_master_volume 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_master_volume. 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_master_volume is provided by the Ableton MCP server (jpoindexter/ableton-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Ableton, 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.
128 Ableton tools catalogued and risk-classified — across an index of 43,000+ MCP servers.