apple_music_playback

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already cover the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true, idempotentHint=false), lowering the bar. The description adds two useful behaviors beyond the enum: play also resumes, and playback can stream audio. However it says nothing about required Automation permissions, what happens when nothing is playing, or why non-idempotency matters for repeated calls.

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?

Three short sentences with the action list front-loaded and zero filler. Each sentence carries distinct information: actions, optional targeting, and streaming behavior.

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?

No output schema exists, so the description would need to carry more behavioral weight for a stateful, open-world mutation tool. It covers the actions and targeting but omits permission requirements, error/no-active-playback behavior, and the implications of non-idempotency.

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 0%, so the description should compensate; it does so only partially. It explains that play can target a track or playlist (mapping trackId/playlistId), but gives no format for those IDs, no indication of mutual exclusivity, and no statement that pause/stop/next/previous ignore them.

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 ('Control Music playback') and enumerates the exact actions (play/resume, pause, stop, next, previous), which maps directly to the action enum. It is clearly distinguishable from siblings like apple_music_get_playback_state and apple_music_set_volume, though it does not name those siblings explicitly.

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?

Usage is implied by the enumerated actions, and the note that 'Play optionally targets one track or playlist' hints at when trackId/playlistId apply. There is no guidance on when to choose this tool over get_playback_state or set_volume, and no exclusions or prerequisites are stated.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.