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 so: it discloses the全市场 vs single-stock scope switch, the default-to-latest-trading-day behavior, and — critically — the non-obvious fallback that an empty result returns quote meta-info instead of an error, plus how to detect it (presence of TurnoverPrice/BuySalesDepartment).

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 purpose and field list, then usage triggers, then parameter warnings, then sibling differentiation. Every ⚠️ block covers a distinct failure mode; nothing is redundant filler.

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?

With an output schema present the description needn't enumerate normal return fields, and it still goes further by explaining the degenerate no-block-trade response. For a 2-param, zero-annotation tool this is complete.

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 100% and both parameters already document their empty-value semantics ('留空=当日全市场', '留空=最近交易日'). The description restates the same semantics rather than adding format, validation, or example detail, so the baseline 3 applies.

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?

Opens with a specific verb+resource (大宗交易成交明细) and enumerates the returned fields (成交价/成交量/成交额/折溢价率/买卖方营业部). It explicitly distinguishes itself from the closest sibling: 'ashare_fund 的大宗只是概览一行；本工具是逐笔明细'.

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 concrete user-intent triggers ('有没有大宗交易/折价还是溢价成交/谁在接盘/机构席位'), states the when-not condition via the ashare_fund comparison, and explains both optional-parameter defaults. An agent knows exactly when to route here.

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