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

Goes beyond the annotations by disclosing a key side-effect boundary: cancellation does NOT trigger a refund, and refund requests must be routed to human support via email. That is genuinely useful context an agent cannot derive from readOnlyHint=false / destructiveHint=false / idempotentHint=true. It does not mention auth requirements or what state the order ends in, so it falls short of a 5.

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 tight sentence with the action front-loaded and the refund/feedback caveat following. No padding, though the refund and feedback points could be split for faster scanning.

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?

An output schema exists and annotations cover safety/idempotency, so the description doesn't need to explain returns. But for a mutation tool with three undocumented required parameters, the description leaves an agent guessing about credential and request_key semantics, which is a meaningful completeness gap.

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 description coverage is 0% and there are three required parameters (credential, service_id, request_key) with only regex patterns to hint at their form. The description says nothing about any of them — not what credential is, not that service_id must be an LX- identifier, not what request_key is for (idempotency). This is a clear miss against the low-coverage compensation requirement.

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 and resource ('取消...任务' = cancel a not-yet-completed task), which is distinct from sibling tools like create_order, get_order, request_change, and wait_order. It doesn't explicitly contrast against the nearest sibling (request_change), but the action and its scope are unambiguous.

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?

Adds one precondition ('尚未完成的任务' — only tasks not yet finished) which implies when the tool applies. However, it never names an alternative for related needs such as changing or refunding an order, so the agent must infer the routing (feedback/refunds handled by email) without a tool-level comparison.

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