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

Annotations already declare readOnly/idempotent/openWorld/no-destructive, so safety is covered. The description adds genuine behavioral context: cross-source deduplication and what each record carries (versión, motor, consumo, oportunidad flag vs equal cars, ML guide price, seller-declared risks with the literal phrase, links) – valuable since there is no output schema.

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?

One dense sentence that front-loads scope (all of Uruguay, named sources) then the dedup rule, then the payload. Nothing is wasted and no sentence merely restates the name.

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 24-parameter, zero-required search tool with no output schema, the description covers the two things the schema cannot: deduplication behavior and the shape of each returned listing. It omits pagination/result-limit expectations, which is the only notable 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?

Schema description coverage is 100% across all 24 parameters, including enum meanings (rural = familiar, dealer = automotora) and cross-field dependency (model requires brand). The description adds no parameter-level meaning beyond that, so the baseline 3 applies.

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?

States a specific verb (busca) and resource (autos usados) with an explicit geographic scope (todo Uruguay) and enumerates the underlying sources, plus a dedup guarantee. It never names a sibling, so the agent gets no direct routing signal versus find_car_opportunities or car_market_report.

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 mention that one car appearing in several sources is returned once implies this is the broad discovery search, and the 'todo Uruguay' framing suggests a wide-net query. But there is no explicit when-to-use/when-not and no reference to the narrow siblings (find_car_opportunities, get_car, car_market_report), which is exactly what an agent with 29 tools needs.

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