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

Annotations already declare readOnly, idempotent, non-destructive and non-open-world, so the safety profile is covered. The description adds the data scope (what the profile contains) but says nothing about lookup failure, ambiguous name matches, rate limits, or the fact that at least one identifier is effectively needed despite zero required parameters.

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?

Two sentences, both earning their place: the first front-loads the returned fields, the second handles identification and routes to the fallback tool. No filler or repetition.

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 usefully enumerates the profile contents, which is exactly what the agent needs to judge whether this tool returns what it wants. The gap is that zero required parameters are declared while the prose implies one identifier is mandatory, and no failure behavior is described.

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 description coverage is 100%, so the baseline is 3. The description's note on identifying a company by name, KRS or NIP largely restates the schema, which already labels 'name' as the fallback when KRS/NIP is unknown; no extra format, priority, or conflict-handling detail is added.

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 plus resource ('get the registry profile of one Polish company') and enumerates the fields returned (legal form, PKD, share capital, representation rules, VAT status, financials). It also scopes itself away from the EU-funds/grants/tenders siblings by framing the output as a registry profile rather than a program-specific dataset.

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?

Explicitly names an alternative and the condition for it: 'For earlier years or full statements use get_financials.' It also gives the three acceptable lookup keys, which tells the agent how the tool is invoked. It stops short of saying when NOT to use this versus the get_company_eu_* siblings, so a 5 is not warranted.

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