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

The readOnlyHint annotation already signals a safe read operation. The description adds useful behavioral details beyond the annotation, such as the sort order (by year descending) and the specific fields included for each fiscal year (status, fiscal result, revenues, expenses, depreciation, capped depreciation, deficit carryforward). This enhances transparency without contradicting 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, focused sentence that front-loads the primary purpose and lists the returned data fields succinctly. Every word contributes value, with no filler or redundant content.

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 (no params, no output schema), the description fully covers what the agent needs to know: what the tool lists, how results are ordered, and what fields are included per fiscal year. There are no obvious gaps for invoking this tool correctly.

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 tool has zero parameters, so the schema is trivially complete. The baseline for 0 params is 4; the description doesn't need to add parameter-specific semantics since there are none.

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 clearly states the action (lists all fiscal years), the scope (user's fiscal years), and the sorting order (descending year). It distinguishes from sibling tools like get_fiscal_year, which targets a specific year, making the tool's purpose unambiguous.

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 context for use is implicitly clear: this is the tool to list all fiscal years, as opposed to get_fiscal_year for a singleton. It doesn't explicitly name alternatives or exclusions, but the list-versus-get distinction is reasonable from the description alone.

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