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

The description is consistent with the annotations (readOnly, idempotent, non-destructive) but adds no additional behavioral details such as authentication requirements, rate limits, or potential side effects. Since the annotations already cover safety, the description contributes minimal extra transparency.

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, concise sentence with no unnecessary words or repetition. It efficiently conveys the core purpose.

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 description is adequate for a simple lookup tool, but it lacks details about the output structure, what specific MEI data is returned, and the parameter constraints. Given the absence of an output schema, the agent has limited information about the expected response.

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 description mentions that data is provided 'por CPF ou CNPJ', which indicates that either parameter can be used. However, it does not clarify whether one is required, if both can be provided simultaneously, or the expected format. The schema also has no required fields, leaving ambiguity.

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 that the tool retrieves MEI data by CPF or CNPJ, which is specific and unambiguous given the tool name and sibling context. However, it does not explicitly use a verb like 'consult' or 'retrieve', but the implication is strong.

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 no guidance on when to use this tool versus the many sibling consultas_* tools. There is no mention of criteria like 'use when the entity is an MEI' or alternatives for other tax regimes. The choice is left to inference from the name alone.

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