consultar_isbn

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

The description discloses it is a read operation returning JSON with specific fields (título, subtítulo, autores, etc.), aggregates multiple sources, and performs local validation of ISBN length. No annotations are present, so the description fully covers 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?

The description is compact (4 sentences) and front-loaded with the core purpose. Every sentence adds value: function, return info, usage cases, and exclusions. No redundancy.

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 single-parameter tool without annotations or output schema, the description covers purpose, usage, return details, and validation. It lacks explicit error handling (e.g., ISBN not found), but the coverage is otherwise comprehensive.

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 input schema already fully describes the parameter 'codigo' (type, format, example) with 100% coverage. The description adds further context about ISBN-10/ISBN-13 acceptance and validation, enhancing understanding beyond the schema.

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 verb ('Consulta'), the resource ('metadados de um livro pelo ISBN'), and the sources (BrasilAPI, CBL, etc.), distinguishing it from sibling tools (consultar_cep, consultar_cnpj, etc.) which focus on other types of queries.

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?

Explicit when-to-use ('quando o usuário fornecer um ISBN e quiser saber sobre o livro') and when-not-to-use (search by title/author, format validation, price/availability) are provided, guiding the agent effectively.

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