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

No annotations are provided, so the description must carry the behavioral disclosure burden. It discloses the three key outputs and the two supported systems, but it does not clarify behavioral details such as whether the down payment reduces the financed principal, the exact return shape, or what costs are excluded (e.g., taxes/fees).

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 three short, purposeful sentences. It front-loads the function, then lists required/optional parameters, and ends with a naming reminder. Every sentence earns its place with no waste.

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?

With no output schema, the description appropriately names the outputs an agent can expect. Given the rich parameter schema, the only notable omissions are how down_payment interacts with property_value in the calculation and the exact structure of the returned result.

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%, so all five parameters already have meaningful descriptions. The tool description only restates which parameters are required/optional and emphasizes using exact English names, which adds no semantic value beyond the schema's existing definitions and examples.

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 opens with a specific verb and resource: 'Calcula financiamento imobiliário SAC ou Price' and then lists concrete outputs (parcelas, juros totais, valor total pago). This clearly separates it from sibling calculators like calculate_installment or compare_loans by restricting scope to real-estate financing with two explicit amortization systems.

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?

Usage is implied through the purpose statement, but there is no explicit guidance on when to choose this tool over related siblings such as compare_loans or calculate_installment. The description does provide useful parameter-level guidance (required vs optional, exact names), but it does not state exclusions or alternative routing.

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