Validar RUT o cédula uruguaya

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

Annotations already cover readOnly, idempotent, closed-world and non-destructive behavior, so the bar is lower. The description adds genuinely new behavioral context with 'No consulta a DGI: es validez aritmética', telling the agent the result is an arithmetic check and not an authoritative registry lookup — critical for trusting the output. It stops short of describing failure modes (e.g. qué devuelve si el dígito no coincide).

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 short sentences that front-load the core action, then the accepted input formats, then the crucial scope caveat. Zero filler and nothing repeated from the schema or annotations.

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 two-parameter validation tool with an output schema (so return values need no explanation) and strong annotations, the description supplies what an agent needs: which documents, input format tolerance, and the non-authoritative nature of the check. Only edge-case behavior (invalid input, what a failed validation returns) is left unaddressed.

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 0%, so the description must carry the parameter meaning, and it does: it ties the digits (12 vs 8) to the two documents selected by 'tipo' and specifies that 'numero' accepts puntos, guiones y comas. This resolves the main ambiguities even though the enum literals 'rut'/'ci' are never named verbatim nor is it stated whether separators count toward the digit total.

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 (valida el dígito verificador) and two concrete resources (RUT de 12 dígitos, cédula de identidad de 8 dígitos) with the country scope. No sibling tool in the list does document validation, and the description makes the numeric/length distinction between document types explicit.

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 implies when the tool applies by naming the two document types and the accepted separators (puntos, guiones, comas), which is useful input guidance. However it never states when to use this versus an alternative lookup, nor what to do for non-Uruguayan documents or invalid formats; usage is inferred rather than prescribed.

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