ads_list_customers

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

With no annotations available, the description carries the full behavioral burden. 'Lists' clearly signals a read-only operation, and 'accessible to the authenticated user' explains the authorization-based scope. It does not mention pagination or output details, but for a zero-parameter list tool the essential behavior is disclosed.

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 filler. Every word contributes meaning: the action, the resource, the scope, and the authentication context.

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 zero-parameter list tool with no output schema, the description is largely sufficient. It clearly states what is returned conceptually—all accessible customer accounts—though it could optionally note that the returned customer identifiers are used by downstream ads_* tools.

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 tool has zero parameters, so the input schema is trivially complete with 100% coverage. The description correctly does not try to invent parameter guidance. Per the guideline, 0 parameters warrants a baseline of 4.

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, 'Lists', and a specific resource, 'Google Ads customer accounts', while adding the important scope qualifier 'accessible to the authenticated user.' This clearly distinguishes it from sibling tools like ads_get_customer, which targets a single customer.

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 clearly conveys the context: use this when you need to enumerate all Google Ads customer accounts the current user can access. It does not explicitly name alternatives or exclusions, but the all-vs-single distinction is strongly implied by the wording.

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