Список групп объявлений

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description usefully discloses the API-level filter requirement, which is genuine behavioral context. However it says nothing about pagination behavior or how autoPaginate interacts with limit, which materially affects how results are returned.

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?

Two sentences, front-loaded with purpose before the requirement, and nothing is padded. However the second sentence only covers one parameter pair while six other parameters go unmentioned, so brevity comes partly at the cost of coverage.

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 7-parameter read-only list tool with a fully documented schema and no output schema, the description supplies the one non-obvious calling rule. Details like the default page size or what autoPaginate returns per page are left to the schema, which is acceptable here.

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 including limit, offset, fieldNames, autoPaginate and client_login is already documented, establishing the baseline of 3. The description only reinforces the ids/campaignIds constraint and adds no semantics for the remaining five parameters.

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 and resource ('Возвращает список групп объявлений'), which cleanly separates it from write siblings like create_ad_group and delete_ad_groups. It does not explicitly name a read alternative such as list_campaigns, so it stops short of the top mark.

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?

Adds a real precondition absent from the schema: at least one of campaignIds or ids must be supplied because the Yandex Direct API demands a selection criterion, with all parameters technically optional this would otherwise be a silent failure. It does not discuss when to prefer listing by campaign vs. by id, or how it relates to sibling list_* tools.

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