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

Annotations already indicate readOnlyHint=true, so the description correctly avoids emphasizing safety. It adds value by mentioning the tool also checks if the refuge is closed, providing behavioral context beyond the annotation.

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 with no redundancy. The first sentence states the main action, the second provides usage context. Every sentence is necessary and efficient.

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 4 required parameters and no output schema, the description is complete enough: it explains what is checked and when to use. Lacks return format details, but the tool is simple enough that the missing output schema is not critical.

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 75%, close to the high threshold. The description does not add meaning beyond the schema's parameter descriptions; it rephrases the purpose without detailing parameters.

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 uses a specific verb 'verifica' (checks) and resource 'Refugio San Bernardo', and clearly states it checks availability for dates and room type, plus whether the refuge is closed. This distinguishes it from siblings like check_closures.

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 provides clear context: 'Útil apenas el usuario menciona fechas para ir a la montaña en Mendoza.' It implies when to use but does not explicitly state when not to use or mention alternatives, though siblings exist.

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