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

Annotations already declare readOnly/idempotent/non-destructive behavior, and the description adds substantial behavioral detail beyond that: chronological ordering, truncation of tramitacao/textos with default limits, inclusion of an aviso when truncating, and count/total fields. This meaningfully informs the agent about response behavior. No contradiction 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 dense but well-structured, front-loading the core operation and using clear mode-by-mode organization. It is long, but nearly every clause earns its place given the tool's tri-mode behavior; a slight trim of repeated schema-level field names would make it tighter.

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 tool with three distinct output modes, the description covers all necessary invocation details: defaults, truncation behavior, ordering, the required parameter's source, and the structure returned under each secao. Combined with the output schema and annotations, an agent has everything needed to call this tool correctly.

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%, but the description goes well beyond the schema: it explains how secao changes the entire return shape, clarifies that limite only applies to tramitacao/textos with distinct defaults, and tells the agent where codigoMateria should come from. This adds real semantic value beyond field names and types.

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 and resource: 'Obtém dados de uma matéria pelo codigoMateria'. It then enumerates the three output modes (detalhe, tramitacao, textos), making the tool's scope clear and distinguishing it from search/list tools like senado_buscar_materias.

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 gives clear context for when to use each section and instructs the agent to obtain codigoMateria via senado_buscar_materias. It does not explicitly state when not to use this tool versus other matter-related siblings, but the section-level guidance is strong enough to route correct usage.

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