Walidacja NIP

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

No annotations are provided, so the description carries the full burden. It does disclose one meaningful trait — no network call and no registry query — which tells the agent the result is purely a format/checksum verdict and not proof the NIP exists. It does not say what happens on invalid input, whether the response is a boolean or a detailed result, or that the number's assignment to a company is not verified.

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 sentence, front-loaded with the core action and ending with the most decision-relevant qualifier. Nothing is wasted and nothing important is buried.

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 trivial single-input validator the description is nearly sufficient, but with no output schema and no annotations it leaves the return value undefined — an agent cannot tell whether a failed check yields false, an error, or a structured reason. One clause about the result shape would close the gap.

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?

The single parameter has 100% schema description coverage ('NIP, może zawierać PL, spacje i myślniki'), so the schema already handles normalization syntax. The description adds nothing about the parameter, which is the expected baseline when schema coverage is this high.

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?

Names a specific verb and resource ('Sprawdza sumę kontrolną polskiego numeru NIP') and adds the scope qualifier 'offline, bez zapytania do rejestru', which implicitly separates it from the registry-backed sibling biala_lista_nip. It stops short of naming the sibling directly, so an agent must infer the routing, but the purpose itself is unambiguous.

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 'offline, bez zapytania do rejestru' parenthetical hints at when this tool is appropriate versus a registry lookup, but there is no explicit statement like 'use biala_lista_nip if you need to confirm the number is assigned to an active taxpayer'. Usage is implied rather than stated.

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