buy_label_from_order

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

No annotations are provided, so the description must convey behavioral traits. It indicates a purchase action (mutation) but does not disclose side effects (e.g., whether it marks the order as shipped, if charges are final, or if it's reversible). The behavioral footprint is partially clear but lacks details on consequences.

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 extremely concise: two sentences that cover purpose, usage rules, and a prerequisite. No redundant or wasted wording.

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 has no output schema and no annotations. Given the complexity (nested parameters), the description does not explain the return value or post-conditions. While the purpose is clear, additional context about what the tool produces (e.g., label URL) would improve completeness.

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 has 100% coverage, so parameters are already well-documented. The description adds valuable context by specifying that rate_id must come from get_shipping_rates, which goes beyond the schema. This elevates the score above 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 clearly states the tool's function: printing a label from an existing order (购买面单). It distinguishes itself by explicitly forbidding the alternative create_draft_shipment + pay_shipment flow, making its purpose unambiguous and differentiated from siblings.

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 provides explicit when-to-use guidance: must be used when labeling an order, and not the alternative flow. It also specifies a prerequisite: rate_id must be obtained via get_shipping_rates. This is complete and actionable.

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