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

Annotations already mark readOnlyHint=true, idempotentHint=true, and destructiveHint=false, and the description layers substantial behavior on top: no pagination, ordering by quantidade desc, count=0 for empty committees, the return envelope { siglaComissao, tipo, count, parlamentares }, and the non-obvious quirk that codigoParlamentar is ignored when tipo=relatoria. These disclosures go beyond both the schema and the annotations and would cause mis-calls if omitted.

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?

Five dense sentences, each carrying distinct information: purpose, axis choice, return envelope, ordering/pagination/zero-case, parameter quirk, and sibling routing. It is front-loaded with the ranking purpose and contains no filler or restatement of the title.

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 an existing output schema and read-only annotations, the description covers everything needed to call it correctly: valid signature, the tipo default and quirk, the empty-committee edge case, absence of pagination, and cross-tool resolution of both main parameters. Nothing material is left implicit.

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 coverage is 100%, so the baseline is 3; the description adds value by pointing to where parameter values come from ('Descubra a sigla via senado_listar_comissoes; use o codigo do parlamentar em senado_obter_senador') and by reiterating the codigoParlamentar/tipo interaction. This provenance guidance is genuine added meaning, though the schema already documents the core parameter semantics.

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?

States a specific verb ('Ranqueia') and resource (parlamentares por quantidade de matérias numa comissão), and explicitly differentiates from siblings by naming senado_buscar_materias as the alternative for the matters list itself. The description also points to senado_listar_comissoes and senado_obter_senador for parameter discovery, so an agent can distinguish it within the crowded senado_* family.

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 cross-tool routing: 'Para a lista das matérias em si (não a contagem) use senado_buscar_materias' sets a clear when-not condition, and the guidance to resolve siglaComissao via senado_listar_comissoes and codigoParlamentar via senado_obter_senador tells the agent exactly how to prepare valid inputs. This exceeds the 4-bar of clear context without exclusions.

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