Estados do Brasil

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, but the description adds 'live GET against the public IBGE Localidades API' and 'Returns a Markdown table', giving the agent useful behavioral context beyond the structured hints.

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 organized into Features, Examples, Alternatives, and Behavior – every section contributes concrete information without redundancy. It is concise for the amount of guidance provided.

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 listing tool with two optional enum parameters and an output schema, the description fully covers purpose, parameters, examples, alternative tools, and response format. No critical gaps remain.

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 has 100% coverage with Portuguese descriptions and enums, but the description maps region names to codes (e.g., 'Northeast states: regiao="NE"'), explains sortable fields in English, and gives concrete usage examples, adding value beyond the schema.

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 'Lists all Brazilian states from IBGE' – a specific verb+resource that immediately defines the tool. It further differentiates from siblings by naming ibge_municipios and ibge_localidade for related but different queries.

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 'Use a different tool when' section explicitly directs agents to ibge_municipios for municipalities and ibge_localidade for locality details. Examples for no-parameter, region filter, and sort provide clear usage contexts.

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