Экспресс: оценка стоимости

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, covering safety. The description adds important behavioral details: price is returned as a string-decimal, not a number; typical errors (400 address_not_found, 409 estimating.cant_construct_route) are disclosed; and the output fields are listed. This goes beyond the annotations and aids client handling.

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 concise and front-loaded: it immediately states the primary purpose and the key differentiator (no order creation). It then lists return fields and typical errors in a compact, information-dense manner. Every sentence earns its place, with no redundancy.

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 tool with no output schema, the description adequately covers return values (price, currency_rules, distance_meters, eta, zone_id) and common error responses. It also notes the coordinate order and the option to use addresses. It does not exhaustively describe every possible error or edge case, but it provides sufficient context for an agent to use the tool effectively.

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 the schema fully documents all parameters. The description mentions that route points can be coordinates and/or address, which is also in the schema. It does not add any extra meaning beyond the schema, so a baseline score of 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 clearly states the tool's function: 'Первичная оценка стоимости экспресс-доставки (день в день) БЕЗ создания заявки' (primary cost estimate for express delivery without creating an order). It explicitly distinguishes itself from siblings by mentioning the absence of order creation, and specifies the resource (express delivery) and the action (estimation). The mention of returning price, eta, etc., further clarifies its purpose.

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 provides clear context for when to use this tool: for preliminary cost estimation, and explicitly states 'without creating an order' (БЕЗ создания заявки), which serves as a when-not-to-use for order creation. However, it does not explicitly name alternative tools like express_create_claim, so it stops short of a full 5.

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