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

Beyond the readOnlyHint/idempotentHint annotations, the description discloses non-obvious result behavior: complexes are returned first, each item carries a "нашлось" label and complex composition, and omitting location_id hides availability and timing. That is useful context the annotations cannot convey, though nothing is said about result limits or ordering beyond complexes-first.

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 front-loaded with the purpose and searchable fields, then moves to invocation advice and result interpretation, with no filler sentences. It does repeat the location_id requirement already stated in the schema, a minor 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?

With an output schema present, return values need no explanation, yet the description adds result ordering and the meaning of per-item labels, which aids correct selection. For a two-parameter read-only search tool, an agent has everything needed to call it correctly.

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 both parameters are already documented in the schema, including the 1–10 array bound and the location_id reference to lab4u_cities. The description's contribution is mainly the clarification that queries should be discrete keywords rather than a full phrase, which is already implied by the schema's example. 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?

The description states a specific verb and resource ("Поиск анализов и комплексов Lab4U") and enumerates what the keywords can match: name, abbreviation, indicator, or topic. It is clearly a search tool, but it never names lab4u_test_details as the drill-down alternative, so sibling differentiation is left implicit.

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 guidance: pass all needed keywords at once rather than the user's whole phrase, and location_id is mandatory because otherwise availability and timing are invisible. It also says to use the "нашлось" label and complex composition to pick the right item. What's missing is an explicit statement of when to reach for a sibling like lab4u_test_details instead.

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