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

Annotations already declare read-only and idempotent behavior. The description adds valuable context: the service is pay-per-query, requires no authentication, and accesses only public official data. It also clarifies data controller responsibilities under LGPD, which goes beyond the annotation information.

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 three sentences with a clear lead sentence stating the core function. The subsequent sentences add operational and legal context without redundancy, making it appropriately sized and front-loaded.

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 no output schema, but the description could still benefit from stating the return value or the behavior of the 'completo' flag. It covers purpose, access, and compliance well, but lacks details on response format or error cases, leaving some uncertainty.

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%, so the description must compensate. It mentions CPF and NIS as inputs, covering the two required fields. However, the optional 'completo' boolean parameter is not explained, leaving its effect ambiguous and potentially leading to incorrect invocation.

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 tool's function: it verifies the receipt of Seguro Defeso using CPF and NIS. This is a specific verb+resource combination that distinguishes it from the sibling platform tools like authenticate or show_version.

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 provides clear usage context: it is hosted on the platform, requires no credentials, and is paid per query with prepaid credit. It also notes the public nature of the data and LGPD compliance, implying appropriate use. However, it does not explicitly state when not to use it or compare it to alternatives.

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