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

Annotations declare readOnlyHint=true and openWorldHint=true, and the description is consistent with a read-only lookup against external registries. It adds that the output is a condensed risk summary spanning three registry domains, but says nothing about data freshness, rate limits, or what happens when a registry lookup fails.

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?

A single compact sentence that front-loads the purpose and then enumerates contents. No filler, though the colon-separated field list is slightly dense for a summary tool.

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 no output schema, the description does describe the returned content (VAT status, whitelisted accounts, KRS liquidation/bankruptcy/restructuring flags), which is the essential return-value context. It stops short of describing the shape or types of those flags, but the coverage is adequate for callers.

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 0%, so the description carries the burden. It clarifies that 'nip' identifies a Polish contractor and that 'bank_account' is an optional verification input, but it omits format expectations (NIP digit count, bank account/IBAN form), which matters for an untyped string parameter.

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 deliverable ('concise risk summary') for a specific resource ('Polish contractor by NIP') and enumerates the covered data domains (VAT status, whitelisted accounts, KRS flags). It is clearly an aggregate/overview tool versus its single-purpose siblings, though it never names those siblings explicitly.

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?

'optionally verify a given bank account' gives one conditional trigger for the second parameter, which is useful. However, it never says when to prefer this aggregate summary over check_vat_whitelist, vies_check, or get_krs_extract, and gives no prerequisites or exclusions.

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