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

The description provides crucial operational behavior regarding data timeliness ('Ofertas vigentes hoje; last_known traz vencidas há até 30 dias'), which is behavioral context beyond the provided annotations. It clearly defines the geographical scope (Joinville/SC) which is a critical behavioral constraint.

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 information is highly dense and logically structured: Function -> Data Scope -> Examples -> Limitations. No sentence is superfluous, making it extremely efficient.

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?

The definition is complete for its domain. It covers function, data source limits (geography), operational behavior (timeframe), and transaction limits (read-only), giving the agent all necessary boundaries for a correct call.

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?

With 100% schema coverage, the description excels at defining constraints for the parameters. It clarifies that 'product' accepts slug, ID, or text, and hard-limits the 'region' to Joinville/SC, providing semantic depth to the technical schema definitions.

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 defines the tool's core function as comparing products across markets, specifying the output format (cheapest to most expensive). It also implicitly differentiates itself from simple search tools by focusing on comparative pricing and data quality (current vs. last known).

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 tool provides explicit 'when not to use' guidance by stating it only performs consultation and does not handle sales, reservations, or deliveries. Furthermore, it provides concrete usage examples using natural language phrasing, aiding agent adoption.

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