customer_invoices

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

No annotations are present, and the description gives no information about side effects, permissions, rate limits, or whether the operation is read-only. Without explicit disclosure, the agent has no way to know the behavioral expectations.

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, concise sentence with no redundant words. It directly conveys the essential information without any fluff.

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 one-parameter retrieval tool, the description is adequate but not complete. It does not mention any additional context such as output format, pagination, or error handling. Given the simplicity, it meets the minimum requirement but lacks depth.

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 only includes customer_id with no description. The description adds minimal context by mentioning 'for a customer' but does not clarify the expected format, source, or any constraints for customer_id. The schema coverage is 0%, and the description fails to compensate meaningfully.

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 returns invoices for a customer, including payment state and ordering (newest first). This is specific enough to distinguish it from sibling tools like customer_tickets, which deals with tickets.

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 does not provide any guidance on when to use this tool over alternatives. It does not mention specific use cases, comparisons with sibling tools, or any conditions that would make this tool the preferred choice.

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