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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds a genuinely important behavioral fact not in the annotations: the call consumes credits. The five-year coverage window is also useful context. It does not say what happens when filings are missing or the registration number is invalid.

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 short sentences with zero filler, and the resource and scope are front-loaded ahead of the cost caveat. Nothing needs trimming.

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?

A paid lookup with no output schema leaves the agent guessing about the return shape (statement sections, units, currency, ratio set) and about failure modes such as unknown or unfiled companies. Parameters and safety are fully covered elsewhere, so the gap is moderate rather than severe.

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%, and the schema already documents regNo as IČO/CUI and country as an SK/CZ/RO enum. The description only echoes the country list, adding no new meaning about formats, identifier validation, or required entity existence; baseline 3 applies when the schema does the heavy lifting.

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?

Names a specific resource (financial statements) with concrete scope: up to five years of history plus ratios, limited to SK/CZ/RO. It never distinguishes itself from siblings like get_company or get_risk, so an agent must infer whether this is the right lookup for a given question.

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?

There is no when-to-use guidance and no mention of alternatives such as get_company or get_risk. The only usage-like signal is 'Costs credits,' which warns about cost but does not help select the tool.

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