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

With no annotations, the description carries the behavioral disclosure burden. It discloses the exact-match vs filtering behavior and the unfiltered full-list return, which is useful. However, it does not mention response format, match-count behavior, or edge cases such as no results or ambiguous matches.

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?

Two sentences with no filler: the resource is front-loaded and the usage rules are compactly sequenced. Every clause contributes either the purpose or the parameter behavior.

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 simple lookup tool with three optional, fully described parameters, the description covers purpose, search modes, and unfiltered behavior. Since there is no output schema, it could describe the response shape or error handling more explicitly, but the listed rate types imply the return content.

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 positioning municipioId as an exact lookup and uf/nome as filters, and by clarifying that omitting all filters returns the full list. It does not discuss parameter combinations or validation details.

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 begins with a specific verb and resource: 'Busca alíquotas de ITBI, IPTU, escritura e registro de um município brasileiro.' This clearly distinguishes the tool as a municipal rates lookup from the sibling simulation and calculation 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 gives explicit usage context: 'Passe municipioId para busca exata, ou uf/nome para filtrar. Sem filtro retorna a lista completa.' This clarifies how to choose among parameters, though it does not explicitly contrast with sibling tools or state when not to use this tool.

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