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

Annotations already establish the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false), and the description adds meaningful behavior beyond that: the required auth scope, the plan paywall with the concrete `locked`/`upgradeUrl` response on lower plans, and the fact that calls do not consume quota. This materially helps an agent predict whether a call will succeed and what it will cost.

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?

Three short sentences with zero filler: the first states the core purpose, the second covers prerequisites and plan-gated behavior, and the third notes quota usage. Every sentence earns its place, and the most decision-relevant information is front-loaded.

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?

With a single fully-documented parameter, an output schema available, and annotations covering the safety profile, the description covers the remaining context: purpose, auth scope, plan requirements, the locked fallback, and quota behavior. The only notable gap is guidance on choosing this tool over overlapping siblings like `informe`, which is a minor omission for an otherwise complete definition.

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 coverage is 100% — the single required `id` parameter is fully documented in the schema as the 10-character public auction identifier with a validation pattern. The description adds no parameter-specific semantics beyond what the schema already provides, 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?

The description states a specific output — a viability verdict ('Veredicto de viabilidad') with four named analytical axes (cargas, posesión, rentabilidad, titularidad) applied to an auction. This is a specific resource plus implicit verb, clearly distinct from a plain auction lookup, though it does not explicitly name or contrast a sibling such as 'informe' or 'subasta'.

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 gives clear context for when the tool is usable: it requires an authenticated account with scope `informes:read` and a Pro-or-higher plan, and specifies the fallback behavior on lower tiers (Radar/Starter returns `locked` with `upgradeUrl`). It does not provide explicit when-not-to-use guidance or point to alternative sibling tools, but the prerequisites are stated unambiguously.

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