lookup_company

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

With no annotations, the description carries the burden of behavioral disclosure. It does disclose input normalization ('Spaces and dashes are fine — they are stripped') and the list of returned fields, which is useful. However, it omits potential error conditions (e.g., NIP not found on the whitelist), rate limits, or any explicit statement that this is a read-only operation, leaving gaps in transparency.

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 extremely concise: two short sentences explaining the main purpose and one argument explanation. It is front-loaded with the core action and contains no redundant or filler words, making it efficient and easy to parse.

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?

Given the tool's simplicity (single parameter, read-only lookup) and the presence of an output schema, the description covers the essentials well—purpose, result fields, and input format. The only notable gap is the lack of explicit guidance on when to use this tool over sibling check_vat_status, but this is a minor omission for such a straightforward operation.

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 schema only provides the parameter name and type, while the description adds critical semantics: it specifies that the NIP must be a 10-digit Polish NIP and that spaces/dashes are stripped. This fully compensates for the absent schema description, providing an agent with all necessary input details.

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 clearly states a specific action ('Look up a Polish company by NIP'), identifies the authoritative source ('Ministry of Finance VAT whitelist'), and enumerates the returned data (company name, VAT status, address, registration date, bank accounts). This differentiates it from sibling tools like check_vat_status by implying a full profile rather than a single status check.

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 description provides contextual information about the target (Polish company, NIP) but does not explicitly explain when to use this tool versus the sibling check_vat_status or other alternatives. Usage is implied rather than stated, so some ambiguity remains for an agent deciding between tools.

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