Consultar el contribuyente de la API key

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

Annotations already declare readOnlyHint=true and openWorldHint=true. The description adds meaningful context beyond that: the data is implicitly scoped to the caller's API key (hence zero parameters) and the response contents are enumerated. It does not mention rate limits or error behavior, but for a read-only lookup the safety profile is adequately covered.

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?

Two sentences, no filler: the first states what is returned and the second states why it matters. The return-field list is front-loaded and every clause earns its place.

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 values — and it does, listing six concrete fields. Combined with the annotations covering safety, an agent has everything needed to call and interpret this tool.

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?

Zero parameters, so the baseline is 4. The description explains why no input is needed — the taxpayer is derived from the API key — which is useful framing the empty schema cannot convey on its own.

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 ('Devuelve los datos') and a specific resource ('el contribuyente dueño de la API key'), then enumerates the returned fields (RUC, razón social, tipo, ambiente, actividades económicas, domicilio). An agent can distinguish it from siblings like informacion_servidor or consultar_padron, though the description never explicitly contrasts them.

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?

'Sirve para confirmar con qué RUC y en qué ambiente se va a emitir' gives a concrete usage context — pre-issuance verification. No explicit exclusions or named alternatives are provided, so it falls short of the 5 bar.

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