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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so safety is covered elsewhere. The description adds only the 'per ad client' grouping scope and says nothing about return shape, pagination, or result size for what is presumably an open-world listing call.

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?

One short, front-loaded sentence with no filler. It is appropriately sized for a trivial listing tool, though the brevity is partly under-specification rather than disciplined concision.

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 should compensate by saying what a call returns (ad unit ids, names, sizes, status) and whether results are paginated. Neither is present, leaving an agent unable to predict the response for a one-parameter listing tool.

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?

With a single parameter at 100% schema coverage, the schema already documents that property is the AdSense account id from list_properties. The description's 'in the AdSense account' phrasing loosely reinforces that, but adds no syntax, format, or example beyond the schema.

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 names the resource (ad units) and its scope (per ad client in the AdSense account), so an agent can tell it is a listing tool. However, it never states the verb and does not distinguish itself from the closely named sibling adsense_ad_unit_performance, which an agent could easily confuse it with.

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 on when to use this tool versus adsense_ad_unit_performance or adsense_report, no prerequisites, and no exclusions. The agent must infer usage entirely from the name and the required property parameter.

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