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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered structurally. The description adds that values are drawn from catalog streams and broken down by radio/codec/bitrate, which is useful context. It says nothing about result ordering or whether values are deduplicated, so it does not go beyond the annotation-backed baseline.

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 with no filler. It is efficient, though the one-line form leaves room for a brief note on return shape that would have cost little.

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 parameters, no output schema and annotations covering the safety profile, the description supplies the essential information: what is enumerated and from where. A short indication of the returned value format would make it fully self-sufficient, but nothing needed to invoke it correctly is missing.

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, which is the baseline-4 case. No parameter meaning needs to be added, and the description correctly does not invent any.

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 names a specific resource ('qualidades distintas') and scopes it to the catalog's streams, then enumerates the facets involved (radio, codec, bitrate). That is enough for an agent to know it returns a distinct-value list rather than a filtered search. It does not explicitly distinguish itself from sibling enumerations like list_languages or list_tags, but the resource itself is unambiguous.

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: it is a lookup/enumeration tool, so an agent can infer it should be called when it needs the set of available quality values. No when-not conditions, prerequisites, or alternatives are stated, so the guidance stays at the minimum-viable level.

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