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

The readOnlyHint annotation already declares the tool is safe, and the description does not contradict it. The description adds source/scope context (official SINAPI data, 27 states) but does not disclose further behavior such as pagination, filtering behavior, or access constraints. With annotations present, this is adequate but not rich.

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 a single front-loaded sentence that states the action, resource, and scope without filler. It is concise and every word contributes to the core purpose.

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 the read-only annotation, a 100% documented two-parameter schema, and an output schema, the description is nearly complete for selecting and invoking this tool. It clearly identifies the resource and scope; only the meaning of 'coverage' and explicit usage conditions are 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 description coverage is 100%: both state and desonerado are fully documented in the input schema. The description itself adds no parameter-level meaning, but because the schema carries the full burden, the baseline of 3 is appropriate.

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 clearly states a specific action ('Consulta' – queries) and resource (SINAPI coverage and official database from Caixa/IBGE), scoped to the 27 Brazilian states. It is specific enough to be distinguishable from the unrelated siblings, though it does not explicitly contrast itself with them.

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?

No usage guidance is provided. The description does not mention when to use this tool versus get_financial_summary or search_plans, nor does it state any exclusions or alternatives. The only implicit cue is the SINAPI scope, which is not enough to guide selection.

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