Sets a track as a folder parent or child in REAPER by specifying folder depth. Use it to organize tracks into collapsible folder groups for cleaner mixes.
Set a track as a folder parent or child.
Args: folder_depth: 0=normal, 1=folder parent, -1=end of folder.
| Name | Required | Description | Default |
|---|---|---|---|
| track_index | Yes | ||
| folder_depth | Yes |
Changes observed during successful MCP inspections.
v1.7.3Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden. It does disclose the meaning of the folder_depth values, which is the core behavioral contract for this mutation, but it omits side effects such as how track ordering/nesting is restructured, whether adjacent tracks must already be contiguous, and whether other tracks are affected. Useful but incomplete for a hierarchy-mutating tool.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Compact and front-loaded: purpose first, then the parameter meaning. No filler sentences. The 'Args:' block is a slightly awkward format but costs little.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
A mutation tool with no annotations and no output schema, one of two required parameters completely undocumented, and an unresolved ambiguity between 'child' and the listed -1/'end of folder' value. An agent cannot reliably call this without guessing at track_index semantics.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, so the description must document both required params. It explains folder_depth (0/1/-1) but says nothing about track_index — not its indexing base, whether it's zero-based, or how it is resolved. Only half the parameters are covered, so it fails to fully compensate for the schema gap.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb and resource: setting a track's folder role. However, the phrasing 'folder parent or child' is not cleanly matched by the enum-like values given (0=normal, 1=folder parent, -1=end of folder) – 'child' and 'normal' aren't obviously the same thing, so the intended semantics are slightly muddled. It is still far more informative than a tautology.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No indication of when to use this versus alternatives, no prerequisites, and no mention of what happens to the surrounding track order. The only guidance is implied by the folder_depth values themselves.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.