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

Annotations already declare readOnly and idempotent, and the description adds genuine behavioral detail: it compares textual descriptions rather than waveforms, results are main mixes from other families, and at most three per album. It also tells the agent to expose listen_url to the user.

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 three focused sentences with no filler. Key behavioral constraints and output advice are front-loaded, and the styling ('DESCRIBED') make the central point memorable. It could drop a dependent clause, but it earns its length.

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 2-parameter tool with no output schema, the description covers the main behavior, the result content (listen_url), and a per-album constraint. Edge-case details like ordering or result count when the ref is not found are not covered, but the information is sufficient for an agent to call it well.

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 schema alone provides full descriptions for both parameters (`ref` and `limit` with min/default/max). The description adds no parameter-specific semantics beyond what the schema already states, so the schema-coverage baseline applies.

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 states a specific verb and resource — finding cues 'close in character' to a given one — and explains the matching basis (editorial description, genres, moods, instrumentation) and the intended use case ('more like this one' moments). This clearly differentiates it from siblings like stye_get_track or stye_search_tracks.

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?

It identifies the natural use case ('more like this one' moments), but does not explicitly compare against alternatives such as stye_search_tracks or say when not to use it. The guidance is implied rather than directive.

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