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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description does not add behavioral specifics like data latency, rate limits, or side effects, but it does hint at the output format (one line per site). Since annotations carry the main safety disclosure and the tool is read-only, the description meets the minimum bar without contradicting annotations.

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 two short sentences with zero extraneous wording. It is front-loaded with the primary output ('One line per site: clicks change, the biggest problem, and what to do'), followed by a targeted use case. This is an efficient, well-structured description.

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 simple tool with one parameter and no output schema, the description provides sufficient information about what the agent can expect: a compact per-site summary with key metrics and recommendations. It does not explain how 'biggest problem' is determined, but that is not essential for calling the tool. The parameter's behavior is covered in the schema, making this reasonably complete.

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 input schema fully documents the only parameter (days), including default, range, and comparison logic, so schema description coverage is 100%. The tool description does not mention the parameter at all, but since the schema is complete, the baseline of 3 applies. No additional semantic value is added by 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 clearly states the tool's output: a one-line summary per site covering clicks change, biggest problem, and recommended action. It also frames the scope as 'all my sites' and highlights suitability for agencies with many sites, which distinguishes it from single-site tools like site_overview or page_check. However, it doesn't explicitly name sibling alternatives, so differentiation is implied rather than explicit.

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 provides a clear when-to-use condition: 'Good for agencies with many sites' suggests it is intended for multi-site overviews. It does not mention when not to use it or explicitly state alternatives, such as using a single-site tool for detailed analysis. This is adequate guidance but leaves comparison to the agent.

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