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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the 'publicado' filter, but does not define what 'proximo' means, how results are ordered, or what happens when no event exists.

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?

A single front-loaded sentence with no wasted wording. For a zero-parameter read-only tool, this is appropriately sized.

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?

Given the simple zero-parameter schema and rich annotations, the core invocation information is present. However, with no output schema, the description could say more about the returned event shape, empty-result behavior, or how 'next' is determined.

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?

The tool has zero parameters, so there are no parameter semantics to explain; the baseline for a parameterless tool is 4. The description correctly avoids introducing unnecessary parameter 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?

States a specific verb and resource: 'Devuelve' plus 'el proximo evento VITUR publicado'. It is clear what the tool returns, but it does not distinguish itself from the very similar sibling vitur-proximos-eventos or from vitur-agenda-evento.

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 singular 'proximo evento' implies the use case of fetching only the next event, but there is no explicit guidance on when to use this versus vitur-proximos-eventos or agenda tools. Usage is therefore inferable but not directed.

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