Счётчики по фильтру

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

No annotations are provided, so the description carries the disclosure burden. It adequately covers the key behavioral traits: the operation is cheap ('один дешёвый запрос'), does not download results, and returns the full count ('полное число объявлений'). It does not overpromise or hide side effects, and the read-only nature is sufficiently implied.

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?

The description is three short sentences, each earning its place: what it does, when to use it, and what it returns. The core behavior is front-loaded, and there is no redundant repetition of schema 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?

Despite the high parameter count, the schema fully documents all parameters, so the description does not need to enumerate them. It provides the missing contextual piece: the return value ('total') and the operational guarantee that this is a cheap count rather than a data-fetching call. For a count tool, this is complete enough for an agent to select and invoke it correctly.

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%, and all 37 parameters already have meaningful descriptions in the schema. The tool description adds no parameter-level detail beyond the generic 'по фильтру', but it does not need to because the schema fully documents each parameter. Baseline 3 is appropriate.

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 verb and resource: 'Считает результаты по фильтру' (counts filtered results) and explicitly distinguishes itself from fetching tools by saying 'не выкачивая их' (without downloading them). It clearly communicates that this is a count-only counterpart to search-like tools, and states the exact return value ('total').

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?

The description gives explicit usage context: use it to 'проверить осмысленность критериев' (validate criteria) and 'сравнить варианты фильтра' (compare filter variants). It implies the alternative is fetching results with search/listing, but does not name those alternatives explicitly or state 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.