get_top_gainers_losers

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states what the tool does but lacks details on traits such as data freshness, rate limits, authentication needs, or output format. For a tool fetching dynamic market data, this omission is significant, though it doesn't contradict any annotations.

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 extremely concise and well-structured: one sentence for the purpose and a brief note on arguments. There is no wasted text, and the information is front-loaded, making it easy to scan and understand quickly.

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's complexity (simple data fetch with no parameters) and lack of annotations/output schema, the description is minimally adequate. It covers the basic purpose but misses key contextual details like return format or data constraints. Without an output schema, the description should ideally hint at what to expect, but it doesn't, leaving gaps in completeness.

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 input schema has 0 parameters with 100% coverage, so no parameter documentation is needed. The description correctly notes 'Args: None,' which adds clarity beyond the schema by explicitly confirming no inputs are required. This is helpful, though not essential, earning a 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 clearly states the tool's purpose: 'Get the top gainers and losers in the US stock market.' It specifies the verb ('Get') and resource ('top gainers and losers'), and the geographic scope ('US stock market') helps distinguish it from siblings like get_forecast or get_weather_alerts. However, it doesn't explicitly differentiate from get_news_and_sentiments or get_news_today, which might also relate to market data, so it's not a perfect 5.

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. It doesn't mention any prerequisites, timing considerations (e.g., market hours), or comparisons to sibling tools like get_news_and_sentiments. Without such context, users might struggle to choose between this and other tools for market-related queries.

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