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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds valuable behavioral context beyond this: it accepts an 'RO' prefix on the CUI, returns specific data categories, and explicitly excludes contact details. This is richer than the baseline and does not contradict any annotations.

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 a single, well-structured sentence. It front-loads the core purpose and then lists inclusions concisely. There is no wasted wording or redundancy, and every clause adds information.

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 (one parameter, read-only, no output schema), the description covers the essential context: what the tool does, what data it returns, and one key limitation. It does not explain the exact return structure or error behavior, but for a single-record fetch this is arguably sufficient. More detail would be helpful but is not critical.

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 has only one parameter (cui) with zero description coverage, so the description must compensate. It does so by stating that the tool fetches by CUI and explicitly noting that an 'RO' prefix is accepted, which adds meaningful format guidance. It does not describe the expected format in full detail (e.g., whether to include spaces), but it covers the key nuance.

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 uses a specific verb ('Fetch'), identifies the resource ('single Romanian company profile'), and clearly lists what is included (identity, address, CAEN activities, financials, data-source freshness). It also states an explicit exclusion ('Does not return contact details'), which distinguishes it from sibling tools like get_company_financials or get_company_status.

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 clearly implies when to use this tool: when you need a comprehensive profile for a single company by CUI. It does not explicitly name alternative tools or state when not to use it, but the exclusion of contact details and the focus on a single company provide useful context. Not quite a 5 because it lacks explicit 'use X instead' guidance.

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