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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds nothing beyond the annotations — no mention of what happens when no financials exist for the requested year, whether partial data is returned, or what the summary contains.

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?

A single efficient sentence with the scope qualifier placed last; nothing is wasted. It is slightly under-specified rather than verbose, but the structure is clean and easy to scan.

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?

For a simple two-parameter read tool with rich annotations and a fully documented schema, most of what an agent needs is present. However, with no output schema, the description gives no indication of what a 'financial summary' returns or how missing-year cases behave, leaving a real gap.

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%: the year parameter documents the closing-year format and the latest-filing default, and company_number documents accepted Belgian formats. The description's 'one accounting year' phrasing only echoes the year parameter, so baseline 3 is appropriate.

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 ('Get') and resource ('financial summary') with a scope qualifier ('one accounting year'). The resource is clearly distinct from siblings like get_company, get_employees, and get_shareholders, though the description does not explicitly name or contrast with any of them.

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 guidance on when to use this tool versus alternatives, nor any prerequisites such as whether the company must exist or whether filings must be available. The only selection logic (year defaults to the latest filing) lives in the schema, not the description.

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