Validar CURP

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

Adds substantial behavior beyond the annotations: a malformed CURP is not an error but returns valida=false with a razon field, there is no RENAPO lookup, and the call consumes 1 token of balance. The token cost explains why readOnlyHint is false despite this being a pure validation, so there is no annotation contradiction.

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?

Four sentences, each carrying distinct payload: scope of validation, cross-check condition, error-semantics, sibling routing, and cost. The most decision-critical information is front-loaded and there is no filler.

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?

No output schema exists, so the description carries the return-shape burden and does so by naming the valida and razon fields and their semantics. Combined with the routing note and cost disclosure, 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?

Schema coverage is 100% with detailed nested-object documentation, so the schema does the heavy lifting (baseline 3). The description still adds meaning by framing the persona object as an optional cross-check against the CURP ('la coteja con esos datos'), which is the key behavioral nuance of that parameter.

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 precise verb+resource (validar la estructura de una CURP mexicana) and enumerates what is checked: longitud, formato, entidad, fecha de nacimiento, dígito verificador. It also explicitly distinguishes itself from the sibling verificar_curp_renapo, so an agent can route correctly without opening either schema.

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?

Gives an explicit alternative and the condition that selects it: 'No consulta RENAPO (para eso usa verificar_curp_renapo)'. It also clarifies the trigger for the optional comparison path ('si mandas persona'), leaving nothing to inference.

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