hetzner_get_invoice_details

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

Annotations already provide safety profile (readOnly, idempotent, non-destructive). The description adds value by specifying authentication requirements (environment variables) and data source (usage.hetzner.com, CSV format), which are beyond annotation scope.

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 only two sentences: one for core functionality and one for requirements. It is front-loaded and contains no extraneous information.

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?

Given the simplicity of the tool (one key parameter) and the existence of an output schema, the description covers the main behavioral aspects and prerequisites. It could be slightly improved by explaining the parameter, but overall it is fairly 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 required parameter 'usage_id' has a clear description in the schema itself, but the tool description does not mention it at all. Schema description coverage is 0%, and the description fails to add any explanatory context 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 clearly states that it retrieves detailed invoice information, specifically line items as CSV from usage.hetzner.com. This distinguishes it from sibling tools like hetzner_get_invoice (likely summary) and hetzner_get_invoice_pdf (PDF format).

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 mentions required environment variables as prerequisites but does not explicitly state when to use this tool versus alternatives like hetzner_get_invoice or when line items are needed. Usage context is implied but not articulated.

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