Buy again (reorder)

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

The description discloses key behaviors: skipping unavailable items and reporting them, and returning the updated cart. However, without annotations, it lacks details on authentication needs, mutation effects, or limits on items. The reporting mechanism is vague, and error handling or side effects are not addressed.

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 efficient sentences with no wasted words. The description is front-loaded with the core action and includes essential details in a logical order.

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 tool with one optional parameter and no output schema, the description covers the main functionality. However, it is missing information on error handling (e.g., if order not found) and authentication requirements, but these are minor given the tool's simplicity.

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 provides 100% coverage for the single parameter, and the description adds significant context: it clarifies that order_id comes from get_purchase_history and defaults to the latest order, enhancing the schema's minimal description.

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 adds all items from a past order to the cart, distinguishing it from siblings like add_to_cart (individual items) and get_cart (retrieve cart). The verb 'add' and resource 'items from a past order' are specific and unambiguous.

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 explains when to use (reorder a past order) and defaults to the most recent order, providing clear context. However, it does not explicitly mention when not to use or prerequisites like having a purchase history, though the sibling tools imply that add_to_cart is for individual items.

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