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

Annotations already cover the read-only and closed-world nature, so the bar is lower. The description adds a useful behavioral detail: it defaults to full retained history. It does not disclose aggregation behavior, bot filtering, or date-range edge cases, but that is acceptable given the annotation coverage.

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 compact sentences: the first lists the KPI set, and the second states the default range behavior. No filler, and the most important scoping information is front-loaded.

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 stats tool with no output schema, the description gives the headline metrics and default range, but it does not describe the response format or clarify how date parameters combine (e.g., whether `days` overrides `from`/`to`). It is minimally adequate but not comprehensive.

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 75%, so the schema handles most parameters. The description contributes the site scope and the 'omit days for full history' default, which adds meaning for the `days` parameter. The `site` parameter itself remains undocumented, and interactions between `from`, `to`, and `days` are not explained.

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 tool's output as headline KPIs for a site and enumerates the specific metrics returned (visits, visitors, pageviews, etc.). It distinguishes this from more specialized siblings like get_timeseries or get_breakdown, though it does not name them explicitly.

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 guidance about when to use this tool versus alternatives such as get_timeseries, get_realtime, or get_breakdown. The only contextual hint is the default full-history behavior, which says nothing about selecting this tool over others.

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