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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior. The description goes further by enumerating what is returned, including image details, customer price, delivery EST window, and substitution policy, which helps the agent anticipate output behavior beyond the schema.

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?

A single, front-loaded, compact sentence covers the full scope of the tool. It is a bit long and packed with items, but every element adds informational value and there is no 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?

The presence of an output schema covers return details, while the description supplements with key behavioral constraints such as country-dependent pricing and EST cutoff-aware delivery. Combined with clear parameter prerequisites, this is complete enough for a read-only lookup tool.

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?

Schema coverage is 100% with high-quality descriptions for gift_id, country, and color. The tool description does not add significant parameter semantics beyond that; it merely contextualizes country as the anchor for pricing and delivery.

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 ('详情内容、图片、价格、预计配送、替换政策、限制') and resource (“单一礼物，一个目的地”), clearly distinguishing it from sibling tools like search_gifts, check_delivery, and get_order_status.

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 implies usage: it is for looking up detailed of a single gift for a single destination country. However it does not explicitly state when to use this tool versus alternatives, nor does it mention that search_gifts or check_delivery should be used for discovery or delivery verification.

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