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

readOnlyHint=true and openWorldHint=false already cover the safety profile, so the description is free to add value elsewhere — and it does, by disclosing the shape of each returned item (slug, name, when-to-use, required inputs). Since there is no output schema, that return-content disclosure is genuinely useful context beyond the 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?

One sentence, front-loaded with the action and resource, with the parenthetical efficiently packing the returned fields. Nothing redundant or padded.

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 zero-param, read-only catalog with no output schema, the description supplies exactly what is needed: what comes back and what each entry means. It stops just short of stating that the result set is static/complete or how to use a slug downstream, which would make it fully self-sufficient.

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 zero parameters, which is the baseline-4 case; there is no input to misinterpret. The description correctly implies a no-argument, full-catalog call rather than a filtered lookup.

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: it lists the burofax types that can be written, and enumerates the fields each entry carries (slug, nombre, cuándo usarlo, datos requeridos). An agent can tell it is the catalog/discovery tool rather than the sibling send/status tools, though no sibling is named 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?

Usage is only implied: listing types is naturally the step before redactar_burofax/enviar_burofax, but the description never says when to call it, when not to, or that redactar_burofax is the follow-up consumer of the slugs. Adequate but leaves routing to inference.

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