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

Annotations already declare readOnlyHint=true and destructiveHint=false, so 'solo lectura' merely restates structured data. The description does add one real behavioral constraint — only published and public posts are returned — which usefully warns that drafts/private posts are out of scope, but it says nothing about the resulting error or empty result in that case.

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 clauses; the resource, the lookup key, the visibility constraint, and the read-only nature are all packed in compactly.

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 one-parameter read tool with full schema coverage and read-only annotations, the description covers purpose and scope adequately. The only meaningful gap is what happens for a non-public, unpublished, or nonexistent ID.

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% with a single documented 'id' parameter, so the schema carries the semantics. The description only echoes 'por su ID' without adding format, type, or validity constraints, which is the baseline expectation when the schema is complete.

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 (devuelve) and resource (entrada) plus a scope qualifier (publicada y pública, por su ID) that implicitly separates it from get_latest_posts and search_posts. Sibling differentiation is achieved by the scope wording, though the alternatives are never named.

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 'por su ID' implies the precondition of already knowing a post ID, which is the natural selection rule versus search_posts. However, it never explicitly says when to use this instead of search_posts or get_latest_posts, nor what to do when only a title/slug is known.

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