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

The annotations already declare that the operation is read-only and closed-world, so the remaining burden is small. The description still adds useful behavior: results are limited to the capsules this user can access, and the response fields are named. That is valuable because there is no output schema. Pagination or result limits are not mentioned.

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 a single front-loaded sentence with zero waste: the action comes first, followed by scope and returned fields. Every clause earns its place.

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 parameterless discovery tool whose safety profile is already covered by annotations, the description covers what the agent needs: what it returns and how it feeds the other tools. Only minor gaps remain, such as pagination and whether every listed field is always present.

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 takes no parameters, so the baseline is 4. The description usefully explains why there are no filter parameters: the result set is implicitly scoped to the user's accessible capsules.

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?

It states a specific verb and resource ("Lista las cápsulas") plus the scope ("a las que tiene acceso este usuario") and even the returned fields (nombre, tema, dirección). That is enough to tell it apart from the siblings, but it does not name any sibling explicitly.

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 phrase "nombre (para usar en las otras herramientas)" implies the correct workflow: call this tool first to obtain the capsule names that the other tools need. However, it does not spell out when not to use it or which sibling to prefer in any situation.

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