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

Annotations already declare readOnly/idempotent/closed-world, and the description adds genuinely new behavior: what the natureza field means and why Indisponivel cards carry no value (no official source per territory), plus that upcoming release dates are included. Since there is no output schema, more detail on the response shape would have pushed it higher.

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?

Three sentences, front-loaded with the returned payload and its size, followed by the nature of the natureza field and the release-calendar extra. No filler.

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 no output schema, the description conveys the payload contents (ten named indicators + natureza + próximas divulgações) well enough to call it confidently. Minor gaps remain around payload structure and ordering, but nothing an agent needs to invoke it 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 schema already documents both year (default = most recent) and territoryId ('br', region, or lowercase UF sigla). The description adds nothing beyond 'num ano', so the baseline 3 applies.

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?

Names a specific verb and resource (devolve os 10 indicadores-chave de um território num ano) and enumerates exactly which indicators are returned, so an agent can distinguish it from compare_indicators or get_indicator_series without opening a schema.

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 scope (one territory, one year, all key indicators) implies when to use it, but it never states when to prefer siblings like compare_indicators, get_indicator_series, or get_indicator_latest, nor any exclusions.

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