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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, covering the safety profile. The description adds only the data source (zakupki.gov.ru), which is identity context rather than behavior — nothing about auth needs, rate limits, or what a hit/miss looks like.

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?

A single front-loaded sentence with zero filler, and the register/purpose leads before the parameter. It is efficient, though its brevity borders on under-specification rather than true conciseness.

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, read-only lookup with annotations covering safety, the description is minimally adequate. With no output schema, it says nothing about the result shape (e.g. whether a supplier is listed), which is the main thing an agent would want to know before calling.

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 coverage is 100% and the inn parameter's pattern and 10/12-digit meaning are documented in the schema itself. The description only echoes 'по ИНН', adding no syntax or format detail beyond the structured field, so the baseline 3 applies.

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 (Проверка — check) and a named resource (реестр недобросовестных поставщиков / РНП ЕИС at zakupki.gov.ru) plus the keying parameter (по ИНН). This is clearly distinguishable in kind from unrelated siblings like bik_lookup or currency_rate, but no sibling (e.g. check_zakupki_org, which is also zakupki-related) is explicitly differentiated.

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 function statement implies the use case (vetting a supplier against the RNP), but there is no explicit when-to-use, when-not-to-use, or routing to any alternative registry check (check_zakupki_org, check_sanctions_org, etc.). No guidance is given for when this register is the right one to consult.

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