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

Beyond the annotations (readOnly, idempotent, non-destructive), the description adds important behavioral details: it is pay-per-query, requires no platform credentials, sources official data, and includes legal responsibilities under LGPD. This provides transparency about cost and data handling.

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 verbose, containing redundant legal and operational disclaimers (e.g., 'não é dado sigiloso', 'cliente é o controlador dos dados') that could be condensed. It is not front-loaded effectively; the core action is buried among multiple clauses.

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?

It covers the tool's purpose, official source, cost, and data sensitivity, but lacks specifics about what 'legal' means (e.g., IMEI blocked status), the return format, or error conditions. Given no output schema, some ambiguity remains, but the basics are present.

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 only parameter 'imei' is not mentioned or explained in the description. While the parameter name is self-explanatory, the description adds no meaning about its format, validation, or purpose. Schema coverage is effectively 0%, and it does not compensate.

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 queries for legal cellphone status via Anatel at an official source. The verb 'consultar' and resource 'celular legal' are specific, and it distinguishes from generic sibling tools by naming the regulatory context.

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 mentions it is a paid service ('pague por consulta') and that data is not confidential, but it does not explicitly state when to use this tool versus alternatives or provide conditions for typical use. No clear 'use this tool when' guidance is given.

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