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

Annotations already declare readOnly, idempotent, closed-world, non-destructive, so the safety profile is covered. The description adds genuinely new behavioral context: the underlying full text is private and only publicly derived counts are exposed, and it explicitly states no text is returned. It does not, however, describe the shape of the returned counts or any limits.

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?

It is short, but it is a single awkward, comma-spliced sentence whose opening clause ('by its private full text, from public derived counts') is hard to parse. Little is wasted, yet the front-loading is confusing rather than orienting.

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 4-parameter tool with no output schema and half its parameters undocumented, the description should explain the return structure (what a 'map' contains) and the meaning of the group and year parameters. It conveys the privacy constraint but leaves an agent unable to predict the response shape.

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 only 50%: 'group' and 'words' are documented in the schema, while 'year_from' and 'year_to' have no descriptions at all. The description mentions 'word rates per year' and 'countries named' but does not explain what group ids refer to or how the year bounds interact with the words parameter, so it fails to compensate for the coverage 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?

The description identifies the resource (ILAM's journal African Music) and the nature of the output (derived counts: AI-labelled content groups, countries named, word rates per year), which is more than a restatement of the name. However, the phrasing 'by its private full text' is opaque and there is no clear verb describing what the tool actually does; an agent must infer it produces an aggregate map rather than retrieving anything.

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?

There is no explicit when-to-use guidance and no sibling is named. The clause 'Never returns text' implicitly routes text retrieval elsewhere (e.g., get_text_passages), which is a useful hint, but the agent is left to infer the selection conditions itself.

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