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

Annotations already declare readOnly/openWorld=false/destructive=false, so the safety profile is covered. The description adds genuinely new behavior: the input is restricted to economic data and age, and no name/DNI/contact data is needed, plus it signals the informed-consent premise behind consentimiento_informado. It stops short of describing the output structure or sensitivity to the parameters.

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 dense sentences, front-loaded with the verdict categories before the conditional behavior and the data-minimization note. Every sentence carries information, though the enumeration of outputs is tight enough to require a re-read.

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 13-parameter, read-only, no-output-schema tool, the description covers what is returned (categories, max price, cuota, effort, costs, gaps) and the key conditional mode, plus privacy constraints. Coverage is strong; the remaining gap is that default-sensitive parameters like plazo_anos and itp_joven are not contextualized in the description.

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 69% schema coverage the schema carries most parameter documentation, but the description adds real meaning not present in the schema: the dual behavior of precio_vivienda (estimate max affordable price when omitted) and the scope of inputs actually consumed (ingresos, deudas, ahorros, edad). It does not explain plazo_anos, tin or itp_joven defaults beyond what the schema already states.

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 ('Evalúa') and resource (compra/viabilidad) and enumerates the four outcome classes and the outputs (precio máximo, cuota, esfuerzo, gastos, qué falta). This distinguishes it clearly from siblings like mortgage_calcular_capacidad or mortgage_calcular_cuota, which produce single figures rather than a viability verdict.

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?

Explicitly defines a conditional usage mode: 'Sin `precio_vivienda` devuelve el precio máximo que encaja', which tells the agent when the tool is a reverse-solve versus a direct check. It does not, however, say when to prefer this over mortgage_prescoring_perfil or mortgage_calcular_capacidad, so the sibling routing is left implicit.

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