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

Beyond the annotations (readOnlyHint=true, idempotentHint=true, destructiveHint=false), the description discloses a data-quality gotcha: the source never publishes the parliamentarian's UF and it always comes null. It also reveals conditional field population (bloco only when leadership is of a bloc; partido only when of a party) and the default no-filter behavior.

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 long but information-dense, with purpose front-loaded and every segment earning its place (return semantics, conditional fields, UF gotcha, filters, sibling routing). It slightly over-duplicates the casa value mapping already present in the schema, which keeps it from a perfect score.

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 output schema covers return structure and annotations cover the safety profile, the description fills all remaining gaps: field semantics, the UF null workaround, default behavior, and sibling tool routing. Nothing an agent needs to invoke this tool correctly is missing.

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 100%, so the baseline is 3; the schema already documents casa, vigente, codigoParlamentar, and siglaTipoLideranca. The description adds only marginal parameter-level value — confirming the filter set and stating that omitting filters returns all houses.

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 opens with a specific verb+resource+scope — 'Lista as lideranças do Senado, da Câmara e do Congresso Nacional' — making clear it covers leadership positions across all three houses. It differentiates itself from related siblings by explicitly routing bloc composition to senado_listar_blocos and senator data to senado_obter_senador.

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?

Provides explicit when-to-use and alternative routing: 'Para a composição de blocos use senado_listar_blocos' and 'obtenha-a via senado_obter_senador pelo codigo'. The filter guidance ('Filtre por casa..., sem filtros retorna todas as casas') tells the agent exactly how to scope calls.

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