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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world, so safety is covered. The description adds a genuine behavioral detail beyond them: the content is converted from Sanity PortableText into markdown, which tells the agent what format to expect. Auth requirements and pagination 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?

Two short sentences, zero filler, with the core purpose front-loaded and the format detail following. 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?

A single-parameter, read-only fetch whose annotations and schema are complete, and which has no output schema to explain. The description covers purpose and return format adequately; only an explicit pointer to list_blog_posts 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?

Schema description coverage is 100% and only one parameter (slug) exists, so the schema fully documents the input. The description adds no slug format or example beyond what the schema provides, making the baseline 3 appropriate.

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+resource ('Detalhe completo de um post do blog') and clarifies the returned payload (body in markdown converted from PortableText). The detail-vs-list contrast with sibling list_blog_posts is strongly implied by 'Detalhe completo' but the sibling is never 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?

The clause 'Útil pra LLMs lerem o conteúdo na íntegra' hints at when to reach for it (need the full content rather than a listing), but no alternative tool is named and no exclusions are given. Usage is implied, not spelled out.

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