list_accessible_customers

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

No annotations are provided, so the description must fully disclose behavior. It states the output format (digit-only IDs) and purpose, but does not mention any potential errors (e.g., no accessible accounts), rate limits, or other behavioral nuances. This is minimal disclosure for a tool with no safety 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?

Two sentences, no unnecessary words. The first sentence states the action, and the second adds crucial detail about output format and usage. Perfectly front-loaded and efficient.

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?

The tool's complexity is low (no parameters, simple list), and an output schema exists. The description covers the essential purpose and output format. It is adequate but could be slightly improved by mentioning what happens if no accounts are accessible. Still, it is mostly 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 has zero parameters, so schema coverage is effectively 100%. The description adds value by explaining the output format and its usage, which is not captured by the schema alone. Per guidelines, baseline is 4 for zero-parameter tools, and the description meets this.

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 lists Google Ads customer accounts accessible by the credentials. It uses specific verbs and nouns ('list', 'customer accounts') and distinguishes itself from sibling tools like 'get_campaigns' and 'create_ad' by being a discovery tool for account IDs.

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 explicitly mentions the output as digit-only customer IDs to be used as `customer_id` for other tools, providing clear context for when to use this tool. However, it lacks explicit when-not-to-use guidance or alternatives, though given the zero-parameter nature, it's still quite clear.

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