Adjust the velocity of a specific MIDI note by providing track, item, and note indices. Set a new velocity value from 1 to 127 to control its intensity.
Set the velocity of a MIDI note.
Args: velocity: New velocity (1-127).
| Name | Required | Description | Default |
|---|---|---|---|
| velocity | Yes | ||
| item_index | Yes | ||
| note_index | 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?
Annotations include destructiveHint: false, so the non-destructive nature is already declared. The description adds no further behavioral context—no mention of side effects, reversibility, or requirements. It only restates the basic action without expanding on what happens to the note or the item.
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 very short and front-loaded with the action, which is good. However, the 'Args:' section only lists velocity, omitting three required parameters, making it structurally incomplete and potentially misleading. It's concise but not well-structured for a 4-parameter tool.
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?
Given that the tool requires 4 indices (track, item, note) and has no output schema, the description should explain what these indices represent and how to identify the target note. It does not, nor does it mention any prerequisites or validation. The context is far from complete for an agent to use it correctly.
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 for undocumented parameters. It only explains 'velocity' with a range (1-127), leaving track_index, item_index, and note_index completely unexplained. The agent cannot infer what these indices refer to or how to obtain them, making the description inadequate for proper invocation.
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 clearly states the tool's purpose: setting the velocity of a MIDI note. It specifies the resource (MIDI note) and the action (set velocity). While it doesn't explicitly differentiate from sibling tools like set_midi_note or ramp_midi_note_velocities, the focus on velocity is distinct enough for an agent to understand the primary intent.
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 provides no guidance on when to use this tool versus alternatives. It doesn't mention conditions, prerequisites, or compare with related tools like set_midi_note or scale_midi_note_velocities. An agent has no basis to decide between this and other MIDI modification tools.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.