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

Annotations already declare readOnly, idempotent, closed-world and non-destructive, so the safety profile is covered. The description's only behavioral claim is the vague 'com fundamento e premissas', which does not tell the agent whether a legal basis text or a list of premises is returned, nor what the calculation outcome 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?

Two short sentences with no padding, and the purpose leads. However, one of the two sentences ('A conta é feita por código, com fundamento e premissas') is meta-commentary that consumes space without conveying usable information.

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, 0% parameter documentation, and a calculation whose correctness depends on index selection and date semantics, the description leaves critical gaps. An agent could invoke it but could easily pass the wrong date basis or index and never know what the result should contain.

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%, so the description carries the full burden for three required parameters and it does not meet it. It loosely hints at 'índice' and 'período', but says nothing about 'rent' (is it the current rent? a base value?), the exact meaning of adjustmentDate versus the contract start date, or how to choose among IGP-M/IPCA/INPC/IPCA-E.

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 names the resource (rent adjustment) and the mechanism (contract index over a period), which is better than a tautology. But it never distinguishes this tool from the many sibling calculate tools (debt_calculate, loan_review_calculate, undue_charges_calculate) that also take a value and an index, and 'a conta é feita por código' says nothing an agent can act on.

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 statement of when to use this tool, what preconditions apply (e.g. an existing lease with a defined index), or which sibling to use for a different kind of monetary correction. The agent must infer everything from the tool name.

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