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

The annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds no behavioral context beyond purpose: it doesn't mention the 30-day default window, the fact that start/end and days are mutually alternative, or anything about series granularity or gaps. With annotations doing the heavy lifting, this is adequate but thin.

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 sentences with no filler: the identity of the output is front-loaded, then the use case. Every clause carries information.

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, closed-world tool with no output schema, the description conveys what data is returned and in what shape (daily series, per metric, per marketplace, over a period). The only omission is any hint about series length or handling of missing days, which is minor given the fully documented schema.

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 schema already documents all five parameters including defaults, the yyyy-mm-dd format, the marketplace slug list and the days/end_date alternation. The description only echoes the metric list ('comissão, pedidos, cliques ou vendas'), adding no meaning beyond the structured data. Baseline 3 applies.

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 and resource - a daily time series of a named metric per marketplace - and enumerates the metric options, so the agent knows exactly what it produces. 'Série temporal diária' implicitly separates it from monthly or hourly aggregations, but no sibling is 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?

'Use para detectar tendências, picos e quedas ao longo dos dias' gives a clear analytical context for selecting the tool. It offers no when-not guidance and never points to the obvious alternatives among the 19 siblings, such as painel_get_monthly_growth or painel_get_hourly_breakdown, so usage is implied rather than disambiguated.

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