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

Annotations provide readOnlyHint=true, and the description goes well beyond that by disclosing per-tier daily quotas (20/50 anonymous, 100/200 free, unlimited paid), the account key location, and the isError response when limits are exceeded. This is valuable operational behavior that an agent needs before calling the tool.

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 first sentence front-loads the core purpose and content list, while the second and third compactly convey quota tiers and error behavior. The length is justified by the operational constraints, though slightly more concise quota phrasing could earn a 5.

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 one-parameter tool with no output schema, the description compensates by naming the return contents (subject, customer, НМЦК, stages, dates, platform, securities, links) and the quota error behavior. It lacks only explicit when-not-to-use guidance, but this is a minor gap given the simple input contract.

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%: the schema already documents uniqId as 'Внутренний ID извещения (ntfUniqID из search_tenders)', and the tool description repeats the same provenance without adding format, range, or dependency details. The baseline of 3 for full schema coverage 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: 'Детальная карточка извещения о закупке по внутреннему ID' and enumerates the card's contents (предмет, условия, заказчик, НМЦК, этапы и даты, площадка, обеспечения, ссылки). It also ties the identifier to search_tenders, distinguishing it from list/search siblings.

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 phrase 'поле ntfUniqID из результатов search_tenders' clearly indicates this tool is the detail-retrieval step after performing a search, giving the agent a concrete when-to-use signal. It does not explicitly exclude alternatives like get_tender_documents, but the internal-ID prerequisite provides adequate context for selection.

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