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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint, openWorldHint), so the description's main value is disclosing the returned content: AI-generated summary, key points, why it matters, key numbers, dates, and original source links. That is meaningful context beyond annotations, especially with no output schema, though it does not cover error cases or auth requirements.

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 front-loaded with the return payload, then the accepted input, in two efficient Portuguese sentences. The appended English translation is slightly redundant but brief and potentially useful for non-Portuguese readers.

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 simple single-parameter read tool, the definition is complete: annotations carry the safety profile, the schema fully documents the parameter, and the description explains what the response contains. No output schema is needed given the enumerated return fields.

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 a concrete URL pattern ('/historia/<slug>') beyond the schema's generic 'Slug ou URL da história', giving the agent a useful formatting example for invocation.

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 states a specific verb ('Detalhe') and resource ('uma história') and enumerates the exact payload (AI summary, key points, why it matters, key numbers, dates, source links), making it easy to distinguish from siblings like buscar or listar_temas. It does not explicitly name those alternatives, so it falls short of a 5 by the sibling-differentiation criterion.

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 description gives no when-to-use guidance, no prerequisites, and no mention of alternative tools. The only usage hint is the accepted input format (slug or URL), which does not tell the agent when this tool is preferred over buscar or ultimas_historias.

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