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

Annotations already cover read-only/idempotent semantics, and the description adds real value beyond them: the newest-first ordering, the exact set of figures returned, the cost (free), and the PFA/II exclusion. It stops short of stating paging or empty-result behavior, but adds meaningful context.

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?

Three short sentences, front-loaded with the core action and the returned fields, then the cost and the entity-type caveat. Dense field enumeration is justified since there is no output schema, with no filler.

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?

Because there is no output schema, the description appropriately enumerates the returned financial fields and the ordering, and notes which entity types yield no data. Only minor gaps (e.g., behavior on unknown CUI) remain, which is adequate for this complexity.

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?

With a single required parameter at 100% schema coverage, the schema already documents the cui format (with/without RO prefix) and the cauta_firma fallback. The description adds no additional parameter detail, so the baseline 3 applies.

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 resource (all balance-sheet years filed at the Ministry of Finance for a company), the ordering (most recent first), and the fields returned (turnover, net result, employees, equity, etc.). It is clearly distinct from siblings like cauta_firma or profil_firma, though it does not explicitly name an alternative tool.

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?

Usage is implied by the resource description and the free/no-cost note, and it usefully flags that PFAs and IIs do not file balance sheets (an exclusion for entity types). However, it gives no explicit 'use this vs. that' routing or preconditions beyond what the schema's cui description already implies.

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