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

Annotations are absent, so the description carries the full disclosure burden. It does add one genuine behavioral/access trait beyond the schema — '免费工具（无需 Key）' (free tool, no Key needed) — which is valuable. But it does not state that the operation is read-only, mention data freshness/pagination, or describe any behavioral caveats for the six modes.

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?

The description is compact and front-loaded: purpose first, then the parameter value map, then the use-case trigger, then the access note. Each sentence carries information with no filler. The dense type-value list is appropriate for a multi-mode tool, though it could arguably be structured more readably.

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 only one parameter and an output schema present, the description covers the essentials for basic invocation. However, given 20 siblings and modes that overlap dedicated tools (technical vs ashare_technical, valuation vs ashare_sector_valuation), it does not clarify when the overview tool's modes should be chosen over those siblings — a notable gap for correct tool selection.

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?

The schema provides only a bare 'type' string parameter with a default and no enum, and description coverage is 0%. The description compensates fully by enumerating all six valid values and their meanings (summary=画像总评, trade=收盘, interval=多周期, technical=大盘技术, updown=涨跌分布, valuation=估值分位, rotation=风格轮动), which is essential information for an AI agent to invoke the tool correctly.

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?

The description names a specific resource and purpose ('市场总览' — market overview) and enumerates six concrete modes (summary, trade, interval, technical, updown, valuation, rotation) with Chinese semantics. It is clearly distinct from siblings like ashare_quote or ashare_technical because it positions itself as the broad market-level overview, though it never explicitly names a sibling it is not.

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?

The description gives an explicit trigger condition: '用户问今天市场怎么样用这个' (use this when the user asks how the market is today), which is clear usage context. However, it provides no exclusions or alternative routing — e.g., when to prefer ashare_technical over this tool's technical mode — so it stops short of full when/when-not guidance.

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