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

Annotations already declare readOnly/openWorld/non-destructive, so safety is covered. The description adds real behavioral context beyond them: the catalog is the authoritative list of supported professions, a listed direction does not guarantee support for every profession inside it, and an absent profession must not be swapped for another. Return-value detail is rightly omitted since an output schema exists.

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 front-loaded with the when-to-use clause and the return summary, followed by the caveats. The long enumeration of directions (бэкенд, фронтенд, ... маркетинг и HR) is the only padding, though it arguably helps query-to-catalog matching, so it is defensible rather than wasteful.

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 rich annotations and an output schema present, the description only needs to supply intent, usage timing, and caveats — all of which it does. The one remaining gap is that it does not say whether the catalog changes over time or how to reconcile it with the vacancy-listing flow, but nothing essential to calling 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, so there is nothing for the description to disambiguate; per the 0-param baseline this sits at 4. The description correctly describes a no-argument catalog fetch and adds no misleading parameter hints.

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 resource (the HireSeeker professions catalog) and precisely enumerates what it returns: active specializations, groups and supergroups, countries, work formats, and salary ranges. It explicitly contrasts itself with the vacancy tools ('Это каталог, а не список вакансий'), so an agent can separate it from get_vacancies/search_vacancies without inspecting either schema.

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 gives a concrete trigger ('Используйте, когда нужно выбрать профессию для поиска IT или Digital вакансий') plus a workflow rule: match the request against the live catalog before the first search. It also tells the agent to disambiguate rather than substitute a missing profession. It never names a sibling tool as the alternative, so routing remains implied rather than explicit.

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