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

With no annotations, the description carries the full burden of behavioral disclosure. It communicates the core read-only behavior ('Lista') and geographic scope, but does not mention return format, ordering, pagination, or whether all markets are returned without filtering. It is adequate but minimal.

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 with no filler. It efficiently conveys the resource, action, and geographic context.

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 zero-parameter list tool with no annotations and no output schema, the description provides the essential context: what the list contains and where. It could have added more detail about the result structure, but the tool is simple enough that an agent can reasonably invoke it correctly from this description alone.

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 tool takes zero parameters, so there are no parameter semantics to clarify. Baseline is 4 given the empty schema; the description accurately describes what the no-argument tool will do, so there is nothing missing here.

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 verb ('Lista') and a specific resource ('mercados') with a clear scope ('Menor Preço Hoje em Lages, Santa Catarina'). This distinguishes it from sibling tools like search_offers and best_price, which target offers and prices rather than the markets themselves.

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 clear context: this tool is for listing markets tracked by Menor Preço Hoje in Lages, SC. It implies use when the agent needs the full set of markets, though it does not explicitly mention when to avoid it or name alternatives.

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