itunes_list_playlists

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

With no annotations, the description must disclose behavior beyond the obvious read-only nature. It does add the return format (newline-separated) and track counts, which is helpful, but it does not mention sorting order, whether it includes smart playlists or folders, or any potential side effects (unlikely). It is adequate but not rich.

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 highly concise: two sentences that state the purpose and return format. Every word earns its place, with no filler or redundant detail. It is front-loaded and immediately understandable.

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 the tool's simplicity (no parameters), the description covers the essential information: what it lists, the format, and that it returns track counts. The lack of an output schema is offset by the explicit description of the return format. However, it could have clarified whether it includes folders or smart playlists, but that's a minor gap for a simple listing tool.

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?

The tool has 0 parameters, and the schema is empty with 100% coverage. According to the baseline, with 0 params, score 4 is appropriate. The description could add context like whether it includes all playlists from all sources, but its absence isn't a significant 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?

The description clearly states it lists all playlists in the Music library with their track counts. It is specific enough to distinguish from siblings like itunes_get_playlist_tracks (which gets tracks within a playlist) and itunes_create_playlist, though it doesn't explicitly mention filtering or exceptions.

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 implies a read-only listing operation with no parameters, but does not explicitly state when to use it versus alternatives like itunes_search or itunes_get_playlist_tracks. It provides no guidance on context or exclusions, only a basic purpose.

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