Validar IBAN

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

The description discloses the validation algorithm (ISO 7064 mod-97) and the extra Portuguese IBAN check, which is useful. However, with no annotations provided, it does not describe the return format, error behavior, or edge cases, so the description only partially carries the transparency burden.

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 two short, front-loaded sentences with no filler. Every word adds useful information about the tool's purpose and behavior.

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?

The tool is simple with one well-documented parameter, but without an output schema the description should clarify what the tool returns (e.g., boolean, status object, or detailed results). The phrase 'Indica também' hints at output but does not specify its form, leaving some incompleteness.

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?

The schema already covers 100% of the single parameter with a clear description ('IBAN a validar, com ou sem espaços'). The description adds no additional parameter-specific meaning, so the baseline score of 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 ('Valida') with a clear resource (IBAN) and adds the checksum standard (ISO 7064 mod-97) and the Portuguese-specific validity check. This clearly distinguishes it from sibling tools like validate_nif and validate_postal_code.

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 is implicitly clear that this tool is for validating IBANs, and the sibling tool names provide context for alternatives. However, the description does not explicitly state when to use it versus other validation tools or mention any exclusions or prerequisites.

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