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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds genuinely useful behavioral semantics beyond that: the match must be exact and the year only tightens the match. It says nothing about hit format or pagination, but for a registry lookup that is minor.

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?

One dense parenthetical sentence that leads with the resource and match key before the optional qualifier. No filler.

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?

A read-only lookup with four fully documented parameters and no output schema; the description supplies the matching semantics an agent needs. Nothing critical is missing, though spelling/case normalization for 'точное совпадение' is left unstated.

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%, so baseline is 3, but the description adds meaning the schema does not: all three name fields are matched exactly, and the year is a secondary refinement rather than a required filter. That changes the agent's expectation of results.

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 concrete verb (проверка), the exact resource (реестр дисквалифицированных лиц ФНС) and the matching key (по ФИО), which cleanly separates it from the sibling check_disqualified_by_org_name. An agent can pick it without opening a schema.

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?

Usage is implied by the matching rule (exact ФИО match, optional birth year) but there is no explicit when-to-use or when-not-to-use guidance and no alternative is named. Adequate, not generous.

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