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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds real value by specifying the returned field set (radius, schedule components, reminder state, assigned people count), which tells the agent this is a rich read, not just an ID list. It omits whether inactive sites are included and whether results are paginated or sorted, keeping it from a 5.

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?

It is front-loaded with the resource and its fields, then the use cases, with no filler prose. The trailing English gloss "Sites and their schedules." is redundant for a Spanish-language description but is a minor cost.

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?

With no output schema, the description correctly takes on the burden of explaining what comes back, and the field enumeration does that well for a two-parameter read tool. Gaps remain around empty results, ordering, and whether deactivated sites appear, but none of these block a correct call.

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% and both parameters are self-documenting: 'sitio' with a default of all sites, and 'empresa' noted as only needed for multi-company users. The description reinforces the company scoping but adds no syntax, matching, or partial-name behavior beyond what the schema already states, so the baseline 3 applies.

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 names the specific resource (company sites: worksites, branches, clients, posts) and enumerates exactly what each record carries: address, allowed radius, schedule (entrada, retardo después de, salida, días), reminder flag, and assigned headcount. That enumeration makes it unmistakable against siblings like actualizar_horario_de_sitio or cobertura_de_sitio, which operate on subsets of the same data.

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?

It gives concrete trigger phrasings ("¿qué sitios tengo?", "¿a qué hora es la entrada en la obra de Apodaca?") and states the pre-write use case ("antes de dar de alta o cambiar un sitio"), which effectively routes the agent to dar_de_alta_sitio/actualizar_horario_de_sitio afterwards. It stops short of explicit when-not conditions or naming the alternative tools outright, so it lands just below the top.

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