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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so safety is covered. The description adds valuable context: hosted on the platform, no platform credentials needed, paid per query with prepaid credit, returns official (non-confidential) data, and clarifies LGPD responsibilities. This goes beyond the annotations.

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 a single paragraph, reasonably concise, and front-loaded with the tool's purpose. However, it includes legal and payment details that, while useful, could be trimmed or positioned later. Still, every sentence adds relevant context.

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?

Given the tool's moderate complexity (5 optional parameters), no output schema, and useful annotations, the description covers payment, data nature, and legal aspects but lacks param semantics and usage examples. The absence of output schema increases the need for description to explain return behavior, which is not addressed.

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%, and the description mentions no parameters. The schema lists five properties (apf, car, cpf_responsavel, cpf_proprietario, cnpj_proprietario) but without any explanation, leaving the agent to guess their meaning and optionality. The description should clarify that these are search filters or identifiers.

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 states it is a 'consulta' (query) for 'APF Rural' from an official source, which indicates a read operation. However, it does not specify what 'APF' stands for or what the result contains, and it lacks differentiation from sibling tools (though siblings are unrelated system tools).

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 explains the payment model (pre-paid credits) and the LGPD data controller responsibility, but it does not specify when to use this tool over others or provide exclusions. It implies a paid query but no clear guidance on appropriate use cases beyond the general 'consulta' context.

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