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

Annotations already declare this a read-only, non-destructive operation, so the bar is lower. The description adds real value beyond them: it discloses the exact metric scope, that tips/service charges are omitted and why (built from sale items), that amounts are in business currency, and that a Cotlet API key with app access is required.

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?

Front-loaded with the most important information and generally efficient, but there is mild redundancy between the opening line ('Sales, discounts and refunds from the Sales summary report') and the second sentence ('Returns the Sales summary report ...: items sold, sales, discounts and refunds'), which repeats the metric list.

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 report tool with no output schema, the description does an adequate job: it enumerates returned metrics, explains grouping, notes exclusions and currency, and states the auth requirement. Nothing critical is missing, though the return shape is described only in prose.

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 four parameters, and the description only restates group_by groupings that already match the enum. It adds no format, default, or edge-case detail beyond what the schema provides, so the 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?

States a specific verb (returns) and resource (Sales summary report) and enumerates the metrics it produces: items sold, sales, discounts and refunds. An agent can distinguish this from other Fresha financial tools like fresha_list_payouts without opening the schema.

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 strong context (date range, group_by behavior) but never explicitly states when to use this tool versus a sibling, nor names an alternative. It implies usage through scope description only, and the closest thing to routing guidance is the note that tips and service charges are excluded.

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