itunes_get_lyrics

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

No annotations are provided, so the description carries the transparency burden. It discloses a meaningful behavioral trait: embedded library lyrics are tried first, with an instant fallback to a global lyrics database. It does not mention error behavior or return format, but the core lookup behavior is transparent.

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 compact and front-loaded with the main purpose, followed by a useful behavioral note and a clear Args section. Every sentence adds value with no 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 one-parameter tool with no output schema, the description covers purpose, parameter behavior, and fallback logic. It does not explain what happens when no lyrics are found, but the core functionality is sufficiently complete for an agent to select and invoke the 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 input schema only defines an optional string with a default. The description adds crucial semantics: the parameter accepts a title or 'Title Artist' format, is optional, and empty means use the currently playing track. This fully compensates for the 0% schema description coverage.

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 gets lyrics for the currently playing track or for a specified song by title/artist. This specific verb+resource framing distinguishes it from sibling tools like itunes_search or itunes_get_track_metadata.

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 gives clear usage context: use it for lyrics, with an optional song parameter, and fall back to the currently playing track when empty. It does not explicitly name alternatives or exclusion cases, but the intended use is obvious.

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