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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false. The description adds useful behavioral context beyond those annotations: it uses prices from the last calculation (computed_at), is limited to Joinville/SC, and only queries without selling, reserving, or delivering.

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 compact and front-loaded, starting with the core purpose before conditional behavior, examples, and coverage. Every sentence adds value without repetition.

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, two-parameter tool with full schema coverage, rich annotations, and an output schema, the description is complete enough. It covers purpose, freshness of prices, geographic limitation, and the fact that no commercial transaction occurs.

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 the schema already documents market and region. The description still adds meaning by explaining that providing market causes item-level detail for that market, which is conditional behavior not captured by the schema alone.

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 and resource: calculates the cost of the basic basket per market, and with the market parameter it details that market's items. It is clear, but it does not explicitly distinguish itself from siblings such as find_cheapest or compare_product.

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?

It gives clear usage context through examples like 'cesta básica mais barata' and 'quanto custa a cesta no Bistek', and it explicitly limits coverage to Joinville/SC. It lacks explicit guidance on when to prefer this over sibling tools, but the scope and examples make appropriate use clear.

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