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

With no annotations provided, the description carries the full burden. It discloses that non-business days return a reason (feriado bancário or fim de semana) and the next business day. It also specifies the FEBRABAN calendar and mentions specific holidays considered, adding valuable behavioral context beyond the schema.

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 four sentences, with the primary purpose in the first sentence. Each sentence adds value: usage examples, return behavior, and calendar details. There is no wasted wording, and it is well-structured for quick comprehension.

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?

Considering the simple single-parameter tool with no output schema, the description provides enough context for an agent to select and invoke it correctly. It explains the input semantics, the business context, expected output behavior, and the calendar source. Minor gaps like exact return format do not hinder use.

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% because the only parameter 'data' has its format and example described. The tool description adds context for when to use the date but does not add new parameter-level semantics, which is fine given the high schema coverage. Baseline 3 is appropriate.

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 uses a specific verb ('Verifica') and a clear resource ('se uma data é dia útil bancário'), specifying that agencies open normally. It clearly distinguishes itself from sibling tools like feriados_bancarios and verificar_data by focusing on banking business days and providing the next business day if not.

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?

It explicitly gives example user queries ('o banco abre amanhã?', 'quando vence o boleto?') and states 'Use quando...'. While it doesn't name alternative tools to avoid, the usage context is unambiguous. Exclusions are not mentioned but are not necessary given the specificity.

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