Validar un envío sin mandarlo

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

Annotations declare readOnlyHint: true and openWorldHint: true. The description adds behavioral context by specifying exactly what the validation checks (phone format, template existence, variable exactness) and confirms no sending occurs. No contradiction with 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?

Two sentences, front-loaded with the core action and key constraints. Every sentence adds value: first explains what it validates, second clarifies it does not send. No wasted words.

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 validation tool with 5 parameters and no output schema, the description covers the main checks and safety aspects. However, it does not describe the return format or what happens on success/failure. Given the tool's purpose, the missing output schema detail is a minor gap.

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 add meaning. It mentions templateName and toPhone implicitly, and 'variables del BODY y del HEADER' correspond to the variables and headerVariables parameters. However, it does not specify formats or constraints for parameters beyond their role in validation. The description adds some value but not full parameter-level detail.

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?

The description states the specific verb 'Revisa' (validates) and resource 'payload de POST /v1/messages contra la plantilla REAL del catálogo'. It details what is checked (phone format, template existence, variables exactness) and explicitly says it does not send, distinguishing it from siblings like hilo_send_message.

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 says 'Úsala con el payload que genera tu código antes de disparar un envío de verdad', providing clear when-to-use guidance. It also states 'NO envía nada ni gasta créditos', implying it is a safe pre-send test. It does not explicitly mention when not to use or alternatives, but the purpose is clear.

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