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

Annotations already declare this is a safe, read-only, idempotent, closed-world computation, so the safety profile is fully covered. The description adds only the 'estimate' framing and names a 'note' field, which hints at caveats but does not explain the simplifications or the meaning of the returned note. With annotations doing the heavy lifting, a 3 is appropriate.

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 clauses, zero waste, and the core purpose is front-loaded before the return-shape mention. Every sentence earns its place.

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?

An output schema and annotations cover return values and safety, so little more is strictly required. However, for a French housing-aid estimator whose real-world calculation depends on household income, the description never flags that this is a simplified estimate with assumptions, leaving an agent unable to judge reliability.

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% (rent, city_zone with enum meaning, household_size range), so the schema already documents all three parameters. The description adds no parameter-level meaning beyond that, which is the correct baseline when the schema is complete.

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 (Estimate) and a specific resource (French housing aid / APL), with the French expansion spelled out. It is easily distinguished from the large sibling set, including other French benefit calculators like calculate_prime_activite or calculate_pinel_tax_reduction.

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 gives no when-to-use context, no eligibility prerequisites (income, tenant status), and no indication of how it differs from neighboring French-aid tools. The reader only knows what it computes, not when it is the right tool.

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