express_trace

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

No annotations are provided, so the description carries full burden. It mentions it is a paid API with free tier, but does not disclose any behavioral traits such as rate limits, data freshness, or required authentication.

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 short and includes non-essential pricing and API URL, which could be seen as clutter. It is not front-loaded with the core purpose but is still concise.

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 one parameter and no output schema, the description provides minimal viable information: it says the tool tracks express shipments. However, it omits details like the output format, supported carriers, or any constraints, leaving agent uncertain about what to expect.

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?

Only one required parameter 'trackingNumber' is present with 100% schema description coverage (its description says '快递单号' which is 'tracking number'). The description does not add additional meaning, such as format examples or expected input types, so a baseline score of 3 is appropriate.

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 is for express/courier tracking via the Chinese text '快递轨迹查询', and the category '[Travel]' hints at its domain. However, it does not distinguish it from sibling tools beyond the general topic.

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?

No guidance on when to use this tool versus alternative tracking or search tools. It only mentions pricing and a free tier, but no context on appropriate scenarios.

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