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

Annotations already establish the safe read-only, non-destructive, closed-world profile. The description adds real behavioral context beyond that: the data is anonymous, does not identify the entity, does not expose the unbonused TIN, and does not give per-bonus percentages — useful limits on what an agent can expect.

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?

Front-loaded with what the tool lists, then the negative constraints, in three tight sentences with no filler. Every clause carries information; structure is clean and scannable.

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?

There is no output schema, so the description carries the return-content burden, and it does describe the fields a listing includes (type, purpose, bonused TIN, bonification types). Combined with annotations covering safety, an agent has enough to call it correctly.

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 0% schema description coverage the description must compensate, and it does name both parameters, spelling out the 'tipo' enum values (Fija, Mixta o Variable) and the concept of 'finalidad'. It does not enumerate the finalidad values (vivienda_habitual, segunda_residencia), leaving a small gap.

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 and resource: an anonymous list of active mortgage products, and enumerates the fields returned (tipo, finalidad, TIN con bonificación, bonificaciones). It partially distinguishes itself from the mortgage_* siblings by stating 'No evalúa una operación concreta', but it does not name the tool it is not (e.g. banking_buscar_ofertas).

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 exclusion 'No evalúa una operación concreta' implies this is for browsing the catalog rather than assessing a specific case, which points away from the evaluar/simular siblings. However, no explicit when-to-use rule or named alternative is given, so the guidance is only implied.

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