itunes_add_to_playlist

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

With no annotations provided, the description carries the full transparency burden. It discloses the important behavior of searching across all user playlists (not just Library), selecting the first match, and returning status or an error. It could mention mutation side effects or duplicate handling, but it still gives a solid behavioral picture.

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, followed by a concise rationale paragraph, then structured Args/Returns sections. Every element earns its place with no fluff or redundancy.

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 simple two-parameter tool, the description is complete enough: it states the search scope, the selection rule, and the return behavior. Missing details like playlist creation or duplicate handling are not critical given the low complexity, but could add slight confidence.

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 defines 'song' as 'The song title to search for' and 'playlist' as 'The name of the destination playlist,' which is basic but helpful. The narrative adds 'first match' behavior, but parameter docs remain minimal and don't mention matching behavior, case sensitivity, or optional qualifiers.

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 opens with a specific verb and resource: 'Search for a song by title across all playlists and add the first match to the named playlist.' This clearly defines the tool's action and scope, distinguishing it from sibling tools like itunes_move_playlist_track, itunes_remove_from_playlist, or itunes_play_song.

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 when this tool is necessary: tracks may be sourced from Apple Music subscription or iCloud Music Library and not appear in the main Library. It gives context for choosing this tool but does not explicitly name alternatives or exclusion scenarios.

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