Create an empty MIDI item on a track at a specified position and length, returning item info including the new item index.
Create an empty MIDI item on a track.
Args: position: Start position in seconds. length: Length in seconds.
Returns: Object with item info including the new item_index.
| Name | Required | Description | Default |
|---|---|---|---|
| length | Yes | ||
| position | Yes | ||
| track_index | 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 burden of behavioral disclosure. It mentions that the item is empty and that a return object includes item_index, but it omits side effects, track-existence requirements, selection behavior, and error conditions for a mutation 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?
The description is front-loaded with the core action, then lists arguments and return value efficiently. Every sentence is relevant and there is no wasted text.
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?
For a creation tool with three required parameters, no annotations, no output schema, and 0% schema descriptions, the description is too thin. It covers the return value broadly but omits track_index semantics, side effects, and prerequisite conditions.
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 compensate. It adds useful units for two parameters (position and length in seconds), but it does not describe track_index at all, leaving one of three required parameters semantically undocumented.
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?
The description states a specific verb and resource: 'Create an empty MIDI item on a track.' This clearly distinguishes the tool from siblings like get_midi_item, clear_midi_item, and add_midi_note. It does not explicitly name a sibling alternative, so it falls short of the highest clarity tier.
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?
The description explains what the tool does but gives no guidance about when to use it versus alternatives such as add_midi_note or insert_audio_file. There are no prerequisites, exclusions, or context cues to help an agent choose this operation.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.