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

Annotations only declare idempotentHint, so the description carries the behavior burden and does well: it discloses the login requirement, the two-step preview/confirm flow, that no new order is created, channel-specific routing (App self-renew vs web cashier), and blocking states. Return-format details are thin but the key behavioral traits are surfaced.

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?

Front-loads the login requirement and packs the flow, channel, and eligibility into a compact block with no obvious filler. It is dense to the point of being terse, but every clause conveys real information.

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 4-param, no-output-schema mutation/resume tool, the description covers login, the confirm-token flow, channel behavior, and failure conditions sufficiently for an agent to invoke it correctly. Minor gaps remain around output/return rather than core invocation.

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 0%, so the description must compensate. It explains preview/previewHash (reuse params + hash from preview to confirm) and channel 'auto' behavior and app-vs-web routing, but leaves outTradeNo as only implicitly '原订单号' and does not distinguish wap/page enum values, so coverage is partial.

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 (预览/续付) and the exact resource (本人原单), and distinguishes the resume action from get_payment_order used for verification. An agent can tell this resumes an existing order rather than creating one (不新建), though the primary 'resume payment' action is a bit buried behind the preview step.

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?

Gives clear usage: preview first, then re-call with the same params + previewHash and preview=false, plus eligibility exclusions (已付/已发放不能续付) and a verification alternative (get_payment_order核验). It doesn't explicitly contrast against create_payment_order, but the when-to-use context is strong.

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