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

With no annotations present, the description carries the full burden of behavioral disclosure. It usefully says that fixed costs, variable costs, and desired margin are included in the sale-price calculation, but it does not disclose the markup formula, output format, units, or edge-case assumptions, leaving some ambiguity about the exact behavior.

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?

Three short sentences with the core purpose front-loaded and every sentence earning its place: purpose, parameter requirements, and naming instruction. There is no filler, repetition, or unnecessary detail.

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 low-complexity calculator with fully documented parameters, the required/optional split and naming rule are enough for an agent to invoke it correctly. Still, because there is no output schema and no return-value description, the result format is not fully explicit.

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 the schema already documents every parameter and the baseline is 3. The description adds only a re-statement of which parameters are required/optional and an instruction to use exact English names, which is marginally helpful but not substantive new meaning.

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 clear verb and resource — 'Calcula preço de venda com markup' — and enumerates the cost and margin components involved, so an agent understands what the tool computes. It does not explicitly contrast it with sibling calculators, but the markup/price focus is distinct enough among the listed tool names.

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 states required versus optional parameters and the exact English parameter names, which helps invocation. However, it provides no guidance about when to choose this tool over alternatives such as calculate_break_even or calculate_gross_from_net, and no when-not-to-use conditions.

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