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

The readOnlyHint annotation already indicates a safe read operation, and the description adds substantial detail about what is returned: tax result, revenues, expenses, amortizations, opening balances, VAT, form data, and filing information. No output schema exists, so this enumeration is valuable and consistent with the read-only nature.

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 front-loaded with the core purpose and then efficiently lists the return contents in a single sentence. Every listed item adds information, and there is no filler, though the long enumeration slightly reduces conciseness.

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 get-by-id tool with one parameter and no output schema, the description is largely complete: it names the input and thoroughly describes the output contents. It does not cover error cases, authentication needs, or exact response formatting, but those are less critical for this read-only retrieval use case.

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 zero schema description coverage, the description compensates by clarifying that the integer 'year' parameter identifies the fiscal year to retrieve. It adds contextual meaning by specifying 'par son année' and associating the parameter with the fiscal-year concept, though it does not provide range, format, or example values.

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 a specific action ('Retourne le détail complet d'un exercice fiscal par son année') and identifies the resource and the lookup key. It enumerates the contents in detail, which helps distinguish it from list_fiscal_years, though it does not explicitly contrast itself with compute_fiscal_year.

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?

No explicit guidance is given about when to use this tool versus siblings like list_fiscal_years or compute_fiscal_year. The context implies this is for retrieving an existing fiscal year's detail, but the description never states alternatives or exclusions.

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