Get Email Statistics by Subuser

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds no further behavioral context, such as response shape, pagination, or what happens without data, but it also does not contradict the annotations. That makes a 3 appropriate.

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, front-loaded sentence with no wasted words. It clearly states the verb and target, and every word earns its place relative to the tool's purpose.

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?

There is no output schema, so the description carries the burden of explaining what 'email statistics' actually returns. It does not mention metrics, grouping behavior, or date-range implications, leaving an agent to guess whether the response contains counts, rates, or a time series. The schema covers parameters, but the output semantics are underspecified.

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 does not add any parameter-specific detail beyond the schema; 'specific subusers' aligns with the subusers parameter but adds no new meaning to start_date, end_date, or aggregated_by.

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 uses a specific verb ('Retrieve') and resource ('email statistics'), and the qualifier 'specific subusers' distinguishes it from siblings like get_global_stats and the get_stats_by_* breakdown tools. Even the title reinforces the subuser dimension, making the tool's function immediately clear.

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 guidance on when to choose this tool over the many sibling stats tools (e.g., get_global_stats, get_stats_by_country, get_stats_overview). It does not explain that this is the appropriate choice when the user wants per-subuser filtering, nor does it mention any exclusions or alternatives.

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