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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral context by disclosing the exact return shape — ordering, one-line notes, suitable moments, and page/preview/streaming links — which the annotations cannot convey.

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?

A single front-loaded sentence naming the resource first, then the payload. It is dense but every clause (order, note, moments, three link types) describes a distinct returned field, so nothing is filler.

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 and no parameters, the description must carry the return-value burden, and it does by enumerating ordering and the four content elements. Annotations handle safety and scope, so an agent has enough to call and interpret this correctly; only the sibling differentiation gap remains.

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 takes zero parameters, so the baseline of 4 applies; there is nothing for the description to disambiguate. The description correctly adds no parameter discussion and instead spends its words on return content.

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 (list) and resource (all seventeen songs on a named album, in order) plus the return payload, so the agent immediately knows this is the full tracklist for a fixed release. It does not, however, name or distinguish itself from siblings like list_releases, get_song, or find_song, which is the only thing keeping it from a 5.

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 only implied: 'all seventeen songs ... in order' signals this is for retrieving a complete ordered tracklist, but there is no explicit when-to-use, when-not, or alternative named. With four closely related siblings (find_song, get_song, get_lyrics, get_listening_links), explicit routing guidance would be valuable and is absent.

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