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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It reveals that the operation is free ('Grátis') and that it returns CEPs with distance and CNEFE points, implying a read-only search. However, it omits result limits, rate limits, pagination, and error behavior. For a tool with zero annotation coverage, this is thin on behavioral context beyond cost and return content.

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 short sentences with zero waste; the core function is front-loaded and the 'Grátis' note is a single economical add-on. Efficient and easy to scan. Slightly under-specified given the lack of annotations, but that gap is accounted for in other dimensions, not here.

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 radius-lookup tool, the description covers the core purpose adequately. Gaps remain: since the schema marks zero parameters as required yet the tool logically needs a center (cep or lat/lon), the description doesn't clarify this dependency; it also doesn't describe the return format or result limits, and there's no output schema to compensate. Mostly complete but with meaningful omissions.

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% — all four parameters (cep, lat, lon, raio) carry meaningful descriptions including the either/or relationship ('if cep not provided') and the raio range/default. The tool description adds no parameter detail beyond what the schema already documents, so the baseline of 3 applies. No compensation needed since the schema does the heavy lifting.

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 states a specific function: finding CEPs within N meters of a center point (CEP or lat/lon), returning distance and CNEFE points. This is a clear verb+resource+method. It's specific enough to distinguish from general search tools like 'buscar' or 'empresas', though it doesn't explicitly name siblings like 'proximo' or 'vizinhanca' that could overlap. The 'Grátis' note adds a distinctive trait.

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 guidance on when to choose this tool over alternatives. With overlapping siblings like 'proximo' (nearby), 'vizinhanca' (neighborhood), 'cep', and 'buscar', the description gives no routing signal — it never mentions when not to use it or which sibling covers a different case. The reader must infer usage from the function alone.

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