fipe_brands

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the action (listing brands) but does not disclose any additional behavioral traits such as response format, ordering, rate limits, or side effects. For a read-only listing operation, this is minimal but not contradictory; still, it leaves the agent uninformed about what the returned data will look like beyond the implied list of brand strings.

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 two short sentences with no fluff. The purpose is front-loaded in the first sentence, and the constraint is placed second. Every word earns its place, making it easy for an agent to parse quickly.

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 a single parameter, no output schema, and a straightforward list operation, the description is largely complete. It specifies the allowed parameter values and the core purpose. It does not describe the return structure, but that is not critical for a simple listing tool. It could optionally mention that the response contains brand names, but the lack of this is a minor gap.

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?

The schema only defines vehicle_type as a string with no enum or description (coverage 0%). The description compensates by explicitly listing the valid values ('carros, motos, caminhoes'), which adds critical semantic value beyond the schema. It does not explain the meaning of each value, but they are self-explanatory for the FIPE domain, so this is adequate.

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 the action ('List'), the resource ('FIPE vehicle brands'), and scopes it by 'for a type.' This is specific and distinguishes it from the sibling fipe_price, which deals with pricing. The allowed vehicle types are explicitly enumerated, leaving no ambiguity about what the tool does.

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 description provides a hard constraint on the parameter ('vehicle_type must be one of...') which is useful, but it gives no guidance on when to use this tool versus alternatives like fipe_price. It does not mention that this is for listing brands as opposed to other FIPE operations, nor does it advise against using it for other vehicle types. The usage context is implied but not explicit.

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