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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds what the payload reports (Premium flag plus remaining free AI downloads), but leaves 'no período' undefined — no reset cadence, no units, and no note on what is shown for non-Premium accounts.

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 short sentence, front-loaded with the verb and both returned facts, with no filler or redundancy. Nothing here is wasted or buried.

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-parameter, read-only status tool with no output schema, the description does the essential job of stating what comes back. The only gap is that the reporting period and quota semantics behind 'no período' are never defined, which matters for interpreting a count that resets.

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 schema declares zero parameters with additionalProperties=false, so there is nothing for the description to disambiguate. Baseline 4 applies since the tool takes no input and the description correctly implies a call takes no arguments.

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 names a concrete verb ('Mostra') and two concrete resources: Premium status and remaining free AI downloads. An agent can tell immediately this is a read-only account/quota status tool, distinct from siblings like baixar_midia or aplicar_marca_dagua. It doesn't explicitly rule out siblings, but the specificity of the reported content does the differentiating work.

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?

There is no guidance on when to call this — nothing like 'call before baixar_midia to check remaining free AI downloads' or 'use when the user asks about their subscription'. The agent must infer the trigger from the name and sibling set alone.

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