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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safe-read nature is covered. The description adds no behavioral context beyond that, such as the score range, whether it returns a numeric value, or any limits. With annotations carrying the safety profile, the description contributes nothing extra.

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 one short sentence, which is concise and front-loaded with the main purpose. However, it is under-specified; it earns its place by stating the function but does not include necessary elaboration on parameters or usage, making it too terse for adequate guidance.

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?

With no output schema and zero parameter descriptions, the description should explain return values and parameter semantics. It does neither. The single sentence gives only the basic purpose, leaving the agent uninformed about expected results, edge cases, or the meaning of the 'completo' parameter, making it severely incomplete for a tool with 3 optional params and siblings.

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 input schema has 3 parameters with zero descriptions (schema coverage 0%), so the description must compensate. It mentions 'CPF ou CNPJ' indicating either can be used, but does not clarify whether both can be provided simultaneously, nor does it explain the 'completo' boolean flag. This minimal addition barely assists with parameter understanding.

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: 'Score de crédito de um CPF ou CNPJ.' It specifies the resource (credit score) and the input types (CPF or CNPJ), distinguishing it from sibling tools like credito_dossie or credito_relatorio_pf_completo, which likely provide different report types. It is specific and not a tautology.

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 alternatives, such as whether it should be used for a quick score versus detailed reports from siblings. It does not mention prerequisites, typical use cases, or exclusions, leaving the agent without direction on tool selection.

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