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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the description need not re-establish that this is a safe, closed-world read operation. The description adds nothing about output shape, default behavior, or edge cases beyond what annotations provide, so it only modestly clarifies ordering behavior.

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 concise sentences, front-loaded with the primary action and ordering semantics, followed by a clear purpose statement. There is no filler, repetition, or unnecessary detail.

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 read-only ranking tool with five parameters fully described in the schema, the description covers the essential purpose and intended use case. It does not describe return-value structure or explicit boundaries versus siblings, but those gaps are minor given the annotations and schema coverage.

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 all five parameters are already documented. The description only reinforces that the result is ordered by m² price and does not add new meaning about defaults, enums, or param interactions 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 uses a specific verb and resource: it lists neighborhoods of a city ordered by price per m², and explicitly states the two possible orderings. It conveys the core function clearly, though it does not explicitly contrast itself with siblings like preco_m2 or comparar.

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 phrase 'Serve para responder qual é o bairro mais caro ou mais barato' gives clear use context: use this tool when the question is about the most expensive or cheapest neighborhood. It does not name alternatives or state when not to use it, but the intended scenario is reasonably clear.

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