Append a MIDI effect from the available types to a track's MIDI FX chain with default settings. The action is undoable.
Append a MIDI effect from midi_fx.types to a track's MIDI FX chain, with its default settings. Undoable.
| Name | Required | Description | Default |
|---|---|---|---|
| track | Yes | Track id (UUID string from tracks.list, stable) or 0-based index (shifts when tracks are added or moved). | |
| device | Yes | A name from midi_fx.types, e.g. Arpeggiator. |
Changes observed during successful MCP inspections.
v0.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, idempotentHint=false and destructiveHint=false, so the mutation profile is known. The description still adds genuine value with "with its default settings" (the effect lands unconfigured) and "Undoable" (reversibility), but says nothing about duplicate-add behavior, where in the chain it lands, or failure modes, so it stays at a solid 3 rather than higher.
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?
A single front-loaded sentence with zero filler; every clause (source of the name, target chain, defaults, undoability) carries information.
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 two-parameter creation tool with full schema coverage and annotations covering the safety profile, the description supplies what's needed to call it correctly. It doesn't note that defaults are subsequently changed via midi_fx_set_params, which would fully close the loop with its closest sibling.
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 coverage is 100% and both parameters are fully documented, including the UUID-vs-index tradeoff for track, so the baseline of 3 applies. The description reinforces the device value source (midi_fx.types) but adds no syntax or format detail beyond the schema.
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?
"Append a MIDI effect ... to a track's MIDI FX chain" gives a specific verb and resource, and the reference to midi_fx.types plus "MIDI FX chain" implicitly separates it from the device-level siblings like devices_add and from midi_fx_set_params. It stops short of naming any sibling explicitly, so it isn't a full 5.
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 mention of midi_fx.types implies the agent must look up valid names first, which is useful implied usage. However there is no explicit statement of when to use this versus midi_fx_set_params (configure after adding) or midi_fx_remove, and no preconditions are spelled out.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.