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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely new behavior: quota is not consumed ("Nie zużywa puli") and the exact returned field set is enumerated, which matters since there is no output schema. Pagination/ordering behavior is the only notable omission.

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?

Three short sentences: what it does, what it returns, when to prefer it. The routing guidance is front-loaded at the end of a tight block with zero redundant phrasing.

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 only two parameters, no output schema and full annotation coverage, the description supplies everything still missing: the result shape, the no-quota behavior, and the prerequisite relationship to KRS-number-based tools.

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 both parameters are already documented, and the description's mention of name/NIP/KRS/REGON simply echoes the q parameter. The limit parameter and the 2-character minimum are left entirely to the schema, so no value is added beyond it.

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?

"Wyszukuje spółki z KRS po nazwie, NIP, numerze KRS albo REGON" gives a specific verb, resource and accepted lookup keys, which immediately separates it from record-oriented siblings like firma, sprawozdanie or zmiany.

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?

"Użyj najpierw, gdy znasz tylko nazwę firmy — pozostałe narzędzia wymagają numeru KRS" states the selection condition clearly and explains why this tool comes first. It falls just short of 5 because it refers to "pozostałe narzędzia" generically instead of naming the sibling to use afterwards.

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