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

With no annotations, the description carries the full burden; it does disclose that the lookup is free of charge (不收费) and that results include failure reasons, which signals a read-only diagnostic call. It does not state what happens on a miss (empty vs error) or whether results are cached/paginated.

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 short sentences, zero filler, with the query key and returned fields front-loaded and the cost note trailing. Every clause earns its place.

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 one-parameter read tool with no output schema, enumerating the return fields and the no-charge property covers most of what an agent needs. Missing only explicit routing against list_orders and not-found behavior.

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% and the schema itself gives the format hint (SG20261018…). The description adds only a restatement of "by order number", which is the baseline expectation rather than added meaning.

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?

States a specific verb (查询) and resource (一笔调用/订单) and enumerates the returned fields (状态、金额、耗时、失败原因), so the agent knows exactly what it gets. The singular "一笔" implicitly separates it from list_orders, but the sibling is never named.

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?

Usage is only implied: query by order number for a single order. It never says when to prefer this over list_orders or what to do when the order number is unknown, so the agent must infer the routing.

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