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

The annotation readOnlyHint=true already signals a safe read operation, so the description's additional detail on the tool's comprehensive scope (exemptions, multiple taxes, net calculation) adds meaningful context. It does not contradict the annotation and goes beyond it by describing the tool's behavior as a holistic scenario calculator, though it does not detail limitations like missing data handling.

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 dense but every sentence earns its place: it states the scenario type, gives usage triggers, lists what is calculated, names the symmetric tool, and provides prioritization guidance. It is front-loaded with the purpose and contains no repetitive filler, making it concise despite its length.

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 tool with 15 parameters and no output schema, the description provides a strong high-level overview of the tool's inputs and expected output (up to the net amount). It lacks explicit mention of required parameters or optionality caveats, but the detailed input schema and the description's overall scope make the tool sufficiently understandable for an agent to invoke 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?

Schema description coverage is 100%, with each of the 15 parameters having rich descriptions in the input schema. The tool description adds no parameter-level detail beyond mentioning categories like 'comisión inmobiliaria y la gestoría', but since the schema already fully documents parameters, the baseline score of 3 is appropriate.

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 clearly states the tool's function: it calculates all seller-side costs and taxes for a home sale, including capital gains IRPF, municipal plusvalía (IIVTNU), realtor commission, and gestoría fees, arriving at the net amount received. It explicitly distinguishes this tool from standalone calculators and from its symmetric counterpart 'consulta_compra_vivienda', leaving no ambiguity about its scope.

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 provides explicit use cases with example trigger questions ('voy a vender mi casa/piso, ¿cuánto pagaré de impuestos?'). It also gives clear guidance on when to prioritize this tool over alternatives ('PRIORIZA esta herramienta frente a calculadoras sueltas de plusvalía, IRPF o IIVTNU') and references the symmetric buying-side tool 'consulta_compra_vivienda', effectively conveying when and when not to invoke it.

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