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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the description adds meaningful behavioral context: payment per query, no platform credentials, non-confidential nature of the data, and LGPD controller responsibility. This goes beyond structured 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 concise with three sentences, front-loading the main purpose and then adding payment and data governance details. It is efficient with no filler, though the LGPD sentence is a bit heavy for a brief tool description.

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?

For a simple read-only query tool, the description covers purpose, cost, and legal context, but lacks details on output format, return values, or parameter constraints. Since there is no output schema, these gaps reduce completeness.

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 does not compensate by explaining parameter formats or constraints. Parameters like 'cnpj', 'uf', and 'municipio' are self-explanatory by name, but there is no guidance on formatting (e.g., CNPJ with/without punctuation) or accepted state/municipality representations.

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 performs a CPOM query in an official source, using specific parameters (cnpj, uf, municipio). It distinguishes itself as a Brazilian official data consultation tool, though it doesn't specify what CPOM data is returned or how it relates to sibling 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 provides contextual constraints (hosted by platform, no platform credentials, prepaid credit required) but no explicit guidance on when to use this tool versus alternatives. There is no mention of scenarios that would make this tool inappropriate or exclusions.

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