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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered. The description adds genuine context beyond that: thresholds live in 'Verithic's dated weights file', percentiles are computed 'within the area', and the response carries the three indices plus the figures behind them and the cut-off date. It does not mention result counts or pagination, keeping it out of 5 territory.

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?

Purpose is front-loaded and the constraint and disclaimer follow logically, so structure is sound. However the entire content is duplicated verbatim in Spanish, roughly doubling the length without adding information for an agent that reads either language.

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 correctly carries the return shape (three indices, the underlying figures, cut-off date) and the scoping option. What is missing is result-size/pagination behavior and any signal of ranking order, but for a zero-required-param read tool it is largely complete.

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%, so the schema already documents both comarca and language. The description only echoes the county limitation ('Can be limited to a county') and never mentions the language parameter, adding no syntax or format detail beyond the schema. 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 resource and criteria: towns scoring high on Connections and 'Services nearby' that are cheaper than most, returned with three indices, their underlying figures, and a cut-off date. The verb is implicit (it is a filtered ranking), but the purpose is discernible. It does not differentiate itself from siblings like ranking_por_perfil or buscar_por_presupuesto, so it stops short of a 5.

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 only usage-shaped statement is 'Can be limited to a county' and the disclaimer 'Not a recommendation'. There is no when-to-use, no when-not-to-use, and no reference to the obvious alternatives (ranking_por_perfil, buscar_por_presupuesto) that an agent must choose between.

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