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

Annotations already establish readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds that the studies are free ('gratis') and inventories the catalog's sectors, but says nothing about pagination, result limits, or whether an empty catalog is possible — modest added value on top of the annotations.

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 verb and the core payload are front-loaded in the first clause, which is good structure. The nine-sector enumeration is long but genuinely informative, while the English gloss ('/ Lists available AI-visibility studies (free)') is largely redundant duplication of the Spanish opening.

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 burden of describing return fields — and it does, listing industry, country, date, response count, findings and price. Combined with annotations covering the read-only profile, the 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?

The tool takes zero parameters, so the schema imposes no semantic burden and the baseline of 4 applies. The description correctly implies a no-argument, catalog-wide listing rather than suggesting any filtering.

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 ('Lista los estudios disponibles') and enumerates what each entry contains (industria, país, fecha, respuestas, hallazgos, precio), so the agent knows exactly what comes back. It does not, however, explicitly distinguish itself from the sibling buscar_estudios, which an agent could easily confuse with a plain listing.

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?

'Usala para ver qué datos de visibilidad IA de Argentina y el Cono Sur hay' gives a clear use context and sector coverage, but there is no statement of when NOT to use it and no mention of the obvious alternative, buscar_estudios. Usage is implied rather than routed.

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