Проверка контрагента по ИНН или ОГРН

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

Beyond the readOnlyHint/openWorldHint annotations it adds auth context ('без токена' = no token needed) and a validation behavior (the number is checksum-verified before use). 'Только чтение' merely restates the annotation, but the auth and checksum notes are genuine additions.

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?

Purpose is front-loaded, followed by usage, constraint, and behavioral notes in a logical order. The long output-field enumeration is dense but earns its place because no output schema exists to carry that 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?

With no output schema, the description compensates by enumerating the returned fields, and it also covers the single parameter, the auth model, and input constraints. Nothing an agent needs to call it correctly appears to be missing.

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 baseline is 3, but the description adds meaning the schema lacks: the id is pre-validated by checksum and only INN/OGRN forms (never a name) are accepted. This is a modest but real semantic addition.

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 names a specific resource (ЕГРЮЛ/ЕГРИП ФНС data via INN/OGRN) and enumerates exactly what is returned (name, INN, OGRN, KPP, status, head, region, PDF extract). The purpose is unmistakable, but it never distinguishes itself from the sibling validate_requisites, so it falls short of a 5.

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?

It gives concrete usage contexts (before a transaction, to fill contract or invoice requisites) and a hard constraint (name search is unsupported, an INN or OGRN is required). No alternative sibling tool is named, so it stops short of explicit when-not/alternative routing.

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