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

The annotations already cover read-only and non-destructive behavior, so the description adds value by revealing aggregation details ('Soma os recursos recebidos e quebra por órgão pagador e por mês') and the default date range behavior. This goes beyond the structured annotations by explaining what the tool actually does with the data. No contradictions with 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 and well-structured: it opens with the core purpose, then explains aggregation, followed by an important scope limitation, and ends with the default behavior. Every sentence adds new information without repetition or fluff, making it easy to parse for an AI agent.

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?

Given the lack of an output schema, the description reasonably explains the expected output structure (summed totals broken down by paying organ and month). It also covers the tool's jurisdiction, default date behavior, and aggregation logic. It omits error-handling or format specifics, but these are not critical for a straightforward read-only query tool with such clear annotations.

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?

With 0% schema description coverage, the description compensates by explaining that 'CPF/CNPJ' identifies the beneficiary and 'período' is handled via mes_ano_inicio/mes_ano_fim. It also clarifies that without explicit dates, it defaults to the last 12 months, which gives meaning to the optional date parameters. However, it does not specify the expected date format or validate constraints between start and end dates.

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: 'DESPESAS recebidas por uma empresa ou pessoa (CPF/CNPJ) do Governo Federal' and explicitly describes the aggregation behavior ('Soma os recursos recebidos e quebra por órgão pagador e por mês'). It also differentiates from other tools by limiting scope to the federal executive branch, which helps distinguish it from sibling transparency 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 explicit guidance on scope: 'IMPORTANTE: cobre só o Executivo FEDERAL, não inclui estados nem municípios (cada ente tem portal próprio)', telling the user when not to use this tool. It also explains the default time period behavior ('Sem datas, usa os últimos 12 meses'), which clarifies usage without explicit dates. However, it does not explicitly reference sibling tools or name alternatives within the same portal.

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