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

With no annotations, the description carries the burden of behavioral disclosure. It does state what metrics are returned and that the default scope is full retained history, which adds meaningful context. However, it does not indicate that this is a read-only operation, how date parameters interact, or any limitations on data retention or response size, leaving a partially opaque behavioral picture.

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 sentence that front-loads the list of KPIs and then states the default behavior. There is no filler, and every clause provides information an agent needs.

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 4-parameter tool with no output schema and no annotations, the description is minimally adequate: it communicates the core return values and the default time window. It does not explain how from/to/days combine or why this tool is preferable over sibling tools, so an agent may be uncertain in edge cases.

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 already describes to, from, and days, covering 75% of parameters, and the description adds the 'full retained history' default, which complements the days parameter. Still, the site parameter is left undocumented in both schema and description, and no guidance is given on precedence when multiple time parameters are supplied.

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 clearly identifies the resource (a site) and explicitly enumerates the headline KPIs, so an agent can understand what get_stats returns. The 'headline KPIs' wording implies an aggregate overview, which differentiates it from more specific siblings like get_timeseries or get_breakdown, though it does not explicitly name them.

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 when-to-use guidance and no mention of alternative tools. The only usage-related phrase, 'Defaults to the full retained history,' describes a parameter behavior rather than a decision rule. An agent cannot tell from this description whether to choose get_stats over get_visitors or get_bot_report.

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