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

Annotations already cover the safety profile (readOnly, idempotent, closed-world), and the description adds substantial behavioral detail beyond them: a cap of 10 results, ordering with active companies first, the `more` truncation flag, and the exact fields returned. It also clarifies that sole traders and liberal professions are included, which preempts a plausible misassumption.

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?

Front-loaded with purpose, then format, then return shape, then the `more` caveat — a logical order with no filler. It is a dense single paragraph, however, and the 'F numbers are sole traders'' aside plus the closing sentence about sole traders/liberal professions slightly overlap concepts that could be merged.

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?

There is no output schema, so the description must carry the return-value burden and it does: result count, ordering, and per-entry fields. With annotations covering safety and the schema covering all three parameters, nothing material is missing for correct invocation.

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 100%, so baseline is 3; the description goes further by stating the either/or constraint between name and register_number and that `judet` is optional and only meaningful alongside a name. It does not repeat the register-number format detail, which is already in the schema, but the cross-parameter constraint is genuinely additive.

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 specific verb and resource ('Finds a Romanian company') and pins the distinguishing condition in the title and first clause: when the CUI is unknown, search by name, partial name, county or register number. That cleanly separates it from lookup_company and the other siblings.

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?

Gives explicit selection criteria: use this when the CUI is unknown, 'Give either name or register_number', and hand the returned CUI to the other tools. It also prescribes the follow-up when `more` is true — ask the user for the county or a more exact name instead of guessing — which is exactly the disambiguation guidance an agent needs.

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