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

Adds real context beyond the readOnlyHint/openWorldHint annotations: it discloses that follower and play counts are null rather than guessed, and that each call costs 1 credit. This tells the agent what data is unavailable and the cost, which the annotations do not cover.

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 front-loaded sentences: purpose first, then contents, then caveats. Each carries information; no filler. Slightly compressed purpose but efficient overall.

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?

With no output schema, the description appropriately describes return contents (bio, image, banner, genre) and the null-field behavior, which is enough to set expectations. The only gap is the undocumented cache_max_age parameter.

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 50%; the required 'id' parameter is already well-documented in the schema (id or URL form). The other parameter, cache_max_age, is undocumented in both schema and description, so the description fails to close the remaining 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?

States a clear resource ('Public Apple Music artist page') and enumerates the content returned: editorial bio, artist image, banner, and genre. The resource distinction from album/track siblings is implicit in the content list, though it doesn't name an alternative tool 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?

No explicit when-to-use or when-not-to-use guidance, and no reference to a sibling such as appleMusic_search for resolving an id. The only usage-adjacent note is 'Costs 1 credit,' which flags cost but not selection context.

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