rentabilidade_vs_cdi

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

With no annotations and no output schema, the description carries the full burden of disclosing behavior; it only says the result is a percentage of CDI. It does not state the formula direction, whether inputs should be decimals or percentages, or what the return payload looks like.

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 a single, front-loaded sentence with no filler or repetition. It is appropriately concise for a simple calculator, though it could afford one more sentence of 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 two-parameter calculator with no output schema and zero parameter descriptions, the definition is incomplete: it should specify the formula (investment rate divided by CDI), the input unit convention, and the output format. The current text leaves these to guesswork.

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 0%, and the description does not define the two parameters beyond the self-explanatory names taxa_investimento_anual and cdi_anual. It fails to clarify units or value ranges, so the low schema coverage is not compensated.

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 the tool's purpose: it computes how much an investment yields as a percentage of CDI, which is a specific calculation distinct from merely fetching CDI (get_cdi). It does not explicitly name sibling alternatives, so it stops short of a 5.

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?

There is no guidance about when to choose this tool over rentabilidade_real, get_cdi, or juros_compostos. The intended use can be inferred from the name, but the description offers no context, prerequisites, or exclusions.

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