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

No annotations are provided, so the description carries the full burden and does most of it: it discloses read-only behavior, a paid-tier requirement (专业版 ¥99+), and the important partial-response behavior when date is omitted and same-day data is unpublished. It stops short of describing return shape or rate limits, but the output schema covers returns.

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?

Extremely dense and front-loaded: data fields first, then use case, then two warnings, then scope exclusion and entitlement. Every sentence earns its place, though the telegraphic warning-marker style is slightly harder to scan than plain prose.

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 2-parameter read tool with an output schema, nothing essential is missing: scope limits, sibling routing, entitlement gate, date degradation, and read-only status are all disclosed. An agent has everything needed to call it correctly or redirect.

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%, so baseline is 3, but the description adds real semantic value the schema lacks: it explains why date matters (without it, only identifier fields return when same-day data is unpublished) and gives concrete code formats (hk00700 / usAAPL). This turns a documented parameter into an understood one.

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 the specific resource (卖空股数/金额/比率, with field names ShortShares/ShortAmount/ShortRatio) and its true scope: HK/US equities only. It explicitly distinguishes itself from siblings by declaring 'A 股没有卖空数据' and routing 融券 to ashare_margin_trade, which is critical given the misleading ashare_ prefix.

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 an explicit trigger ('用户问"被做空多少/卖空比率"时用') plus two exclusions: not for A-shares, and use ashare_margin_trade for 融券 instead. It also prescribes passing date to avoid a degraded result, which is a concrete usage rule rather than general advice.

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