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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds genuinely useful behavioral details beyond those annotations: date format 'DD-MM-YYYY neste endpoint,' return values as strings with decimal precision, and '(unclassified)' grouping for sales without UTM.

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 a single compact paragraph with no filler. It front-loads the tool's purpose, then gives grouping/filtering instructions, return fields, and an edge-case behavior, with every sentence contributing necessary 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?

With no output schema, the description responsibly lists the returned metrics and their string/decimal nature, and it documents the main grouping and date parameters. Still, the omission of offer, account, and product semantics leaves part of the invocation contract unexplained, so an agent may not know what those parameters control.

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?

With 0% schema description coverage, the description carries the burden of explaining parameters. It usefully explains group_by with its allowed enum values and start_date/end_date with format, covering 3 of 6 parameters. However, offer, account, and product are completely unexplained in both the schema and the description.

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 opens with 'Analytics de vendas na Cakto: métricas financeiras agregadas por canal/campanha,' clearly identifying the tool as sales analytics with aggregated financial metrics by channel/campaign. This distinguishes it from sibling raw-order tools like cakto_orders_list or cakto_orders_get.

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 clear usage context: group by group_by values and filter by start_date/end_date, with the date format explicitly called out. It does not explicitly name alternatives or state when not to use the tool, but the aggregation focus makes the intended use reasonably clear.

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