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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds context about hosting, prepaid payment, official non-confidential data, and LGPD responsibility. This goes beyond the structured annotations without contradicting them.

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 appropriately sized with several sentences covering purpose, payment, and legal context. It is front-loaded with the core action, though the last sentence on LGPD is somewhat dense and not directly action-relevant.

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 7 parameters and no output schema, the description is incomplete. It omits how credentials work, what a 'guide' contains (e.g., PDF, barcode, amount), and the meaning of each parameter. The required 'placa' is never mentioned, leaving the agent unable to confidently invoke the tool.

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 has 7 parameters with 0% description coverage. The description fails to explain any parameter, including the required 'placa', or the authentication inputs login_cpf, login_senha, pkcs12_cert, and pkcs12_pass. It does not compensate for the missing schema documentation at all.

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 'Guias de IPVA, consulta em fonte oficial' with the verb 'consulta' and specific resource 'Detran PE IPVA guides.' It distinguishes itself from platform-level siblings like authenticate and connect by naming the exact domain and operation.

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?

The description gives useful usage context: 'sem credenciais da plataforma' (no platform credentials needed) and 'pague por consulta com crédito pré-pago' (pay-per-query with prepaid credit). It implies when to use this tool (need IPVA guide data from Detran PE) but does not explicitly name alternatives; sibling tools are generic platform utilities, so this is sufficient.

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