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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds useful behavioral detail beyond those flags: results are sorted newest-first, no parameters returns the 10 most recent items, it is a live GET against the public API, and it returns a Markdown list with a header reporting total count and current page. No contradiction with 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?

The description is long but every section earns its place: purpose, when-to-use, parameter explanations, output shape, concrete examples, and a clear pointer to an alternative tool. It is well-structured with headers and bullet-like lists, front-loads the core purpose, and contains no filler or tautology.

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 read-only list tool with seven optional parameters, the description is complete: it explains the return fields, sorting order, defaults, pagination, max limits, examples, and the single important sibling distinction. The output schema and annotations cover the remaining structured details, so nothing critical is missing for an agent to invoke this correctly.

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%, so the baseline is 3. The description adds semantic value beyond the schema by explaining 'tipo' as 'release' (official publication of survey results) versus 'noticia' (general news), noting 'omit for both', giving explicit date format examples, and clarifying pagination and quantidade behavior with defaults and max. This goes beyond simply restating the schema.

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?

The description starts with a specific verb-resource pair: 'Searches and lists already-published IBGE news articles and press releases.' It clearly distinguishes this from related tools by saying scheduled/upcoming publications belong to ibge_calendario, and it names concrete use cases like finding indicator releases or mentions of 'censo'.

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 context is explicit: 'Use this to find recent IBGE publications or announcements about a survey or topic' and it gives concrete examples. It also names the exact alternative for a different scenario: 'Use a different tool when: Scheduled/upcoming release dates (not yet published) → ibge_calendario.' This is strong when-to-use and when-not-to-use guidance.

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