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

No annotations are present, so the description carries the behavioral burden. It correctly implies a read-only query operation and states the returned content: points, percentage change, and overall market trend. But it does not disclose freshness/source limitations, market-hours behavior, or other constraints, so disclosure is adequate but not rich.

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 entire definition is one focused sentence with no filler. It front-loads the resource and includes the essential return fields, making every phrase informative.

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 zero-parameter query tool with no output schema, the description covers the core: which indices are included and what data will be returned. It stops short of perfect because it says nothing about data timing, source, or trading-hours behavior, and it does not explicitly distinguish itself from the sibling tool in text.

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 tool has zero parameters and the input schema already documents an empty object. The description adds nothing about parameters, but none is needed; per the 0-parameter rule the baseline is 4.

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 uses a specific verb ('查询') and names the exact resource: the three major A-share stock indices (上证指数、深证成指、创指). It is immediately distingushable from the sibling query_stock_quote because the resource category is clearly index quotes, not individual stock quotes.

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 intended use case is evident from the description – obtain real-time quotes for the main A-share indices. However, there is no explicit when-to-use/when-not guidance and no mention of the sibling query_stock_quote or any alternative, so the routing is only implied.

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