get_feature

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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds useful behavioral context that results are aggregated counts grouped by languages, families and genera, but says nothing about behavior on unknown feature IDs or the effect of the optional filters.

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 dense sentence with the verb and resource front-loaded and no filler. It is slightly compressed in the trailing clause ('counted by languages, families and genera'), but every clause carries information.

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 a full output schema and rich annotations, the description only needs to convey purpose and the shape of the analysis, which it does. The remaining gap is not pointing at search_features as the way to obtain the required feature ID, which matters for a tool whose only required parameter is an identifier.

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 description coverage is 100%, so every parameter (family, sample, macroarea, by_macroarea, feature) is already documented in the schema. The description's mention of counting by families and genera is only loosely related to the family parameter and adds no syntax, format, or interaction detail beyond the schema, so baseline 3 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?

States a specific verb ('Describe') and a specific, singular resource ('one feature') and then enumerates the returned content: definition, chapter, authors, and value distributions. This implicitly separates it from the plural search_features, but it never names that sibling to make the distinction explicit.

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: an agent infers it should call this once it already has a feature ID and wants detail plus aggregate counts. There is no explicit 'use this when' or 'use search_features to find the ID first' guidance, and no mention of when-not to use it.

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