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

Annotations declare readOnlyHint: true, so the safety profile is covered. The description adds value by detailing the row fields (échéance, date, capital, intérêts, assurance, total, restant dû) and period totals, effectively describing the output structure in the absence of an output schema.

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 concise, two sentences, with the main purpose front-loaded and specific details following. No redundant or filler 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?

For a read-only retrieval tool with two parameters and no output schema, the description covers the return content and optional filtering. It lacks information on error handling or loan-not-found scenarios, but these are not critical for basic usage.

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 schema has no property descriptions (0% coverage). The description explains the 'year' parameter as an optional filter but does not explain the required 'loan_id' parameter, leaving its role to be inferred from the tool name and context.

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 uses a specific verb 'Retourne' and identifies the resource as the complete amortization schedule of a loan, with an optional year filter. This clearly distinguishes it from sibling compute_loan_schedule, which suggests calculation rather than retrieval.

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 description implies the tool is for retrieving an existing loan's schedule but does not explicitly state when to use it versus alternatives like compute_loan_schedule. No exclusions or alternative tool names are mentioned.

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