orders_get_order_invoice

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

No annotations are provided, so the description carries the full burden. It states the tool fetches an invoice document and billing breakdown, giving some indication of the output scope. However, it lacks any mention of authentication requirements, error behavior (e.g., if no invoice exists), or potential side effects. For a simple read tool, this is adequate but not rich.

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 that immediately states the action and the target resource. Every word contributes value, with no redundancy or filler.

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 tool with one parameter and no output schema, the description adequately conveys the core purpose and hints at the return content (invoice document and billing breakdown). It is complete enough for a simple fetch operation, though it could mention what happens if the invoice is not found or the order is invalid.

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 schema already provides 100% coverage with a clear description for order_id ('Order whose invoice to fetch.'). The tool description does not add additional meaning beyond the schema, so it matches the baseline of 3.

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 ('Fetch') and clearly identifies the resource ('invoice document and billing breakdown') for a given order. This distinguishes it from sibling tools like orders_get_order (which likely retrieves the order itself) and orders_list_orders.

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 implies the tool is for retrieving invoice details for a specific order, but it does not explicitly state when to use this versus alternatives or mention any exclusions or prerequisites. The context is clear but minimal, so it earns an implied-usage score.

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