get_us_market_indices

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

No annotations are provided, so the description carries the full burden. It mentions the return format ('Markdown格式的美股指数列表' - Markdown format US stock index list), which adds some behavioral context. However, it doesn't disclose other important traits like whether this is a read-only operation, if it requires authentication, rate limits, or what specific indices are included. For a tool with zero annotation coverage, this is insufficient.

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 concise with two sentences: one stating the purpose and one specifying the return format. It's appropriately sized for a simple tool with no parameters. However, the structure could be slightly improved by front-loading the return format information more clearly, but it's still efficient with minimal waste.

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?

Given the tool has no parameters, an output schema exists (though not provided in context), and no annotations, the description is minimally adequate. It states the purpose and return format, but for a data-fetching tool, it could benefit from more context on what '主要指数' (major indices) includes or example output. With output schema handling return values, the description meets basic needs but has room for improvement.

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 0 parameters, and schema description coverage is 100% (empty schema). With no parameters, the description doesn't need to add parameter semantics. The baseline for 0 parameters is 4, as there's nothing to compensate for. The description appropriately doesn't discuss parameters.

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 states '获取美股主要指数信息' (Get US stock market major index information), which provides a clear verb ('获取') and resource ('美股主要指数信息'). However, it doesn't distinguish this tool from sibling tools like 'get_us_sector_performance' or 'get_us_stock_realtime_data', which also provide US market data. The purpose is clear but lacks sibling differentiation.

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 provides no guidance on when to use this tool versus alternatives. With many sibling tools focused on US market data (e.g., 'get_us_sector_performance', 'get_us_stock_realtime_data'), there is no indication of when this specific tool for indices is appropriate versus other data sources. No exclusions or prerequisites are mentioned.

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