track_fx_set_param
AI agents use track_fx_set_param 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.
Based on the naming convention 'set_param', this tool likely modifies a parameter value on a track's audio effect/plugin within REAPER DAW. This is a reversible write operation — parameters can be changed back. The blast radius is medium since misuse could alter audio processing settings on a track, affecting the mix. Confidence is reduced due to the empty description.
From the tool's definition Tool name 'track_fx_set_param' suggests setting a parameter on a track's FX (effects). Description is empty, lowering confidence.
Documented attack patterns abuse exactly the kind of access track_fx_set_param 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 track_fx_set_param:
{
"version": "1",
"default": "deny",
"tools": {
"track_fx_set_param": {
"limits": [
{
"counter": "track_fx_set_param_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}track_fx_set_param 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.
track_fx_set_param. 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 track_fx_set_param: 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.
track_fx_set_param 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 track_fx_set_param 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 track_fx_set_param. 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.
track_fx_set_param 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.