weather_now

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

No annotations are provided, and the description does not disclose any behavioral traits such as data freshness, response format, or any limitations (e.g., cities supported). The agent learns nothing beyond 'real-time weather'.

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 includes extraneous operational details (pricing, API URL) that are better placed elsewhere. It is not optimally concise; the core purpose could be stated in a single clear sentence.

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 no output schema and only one parameter, the description should explain the output format (e.g., temperature, humidity) but does not. The tool's simplicity does not fully excuse this lack of return-value context.

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 single required parameter 'city' has a Chinese description in the schema ('城市名'), which is clear. Schema coverage is 100%, so the description adds no extra semantic value. Baseline score of 3 is appropriate.

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 indicates the tool provides real-time weather ('实时天气'), distinguishing it from siblings like weather_forecast and weather_history. However, the inclusion of pricing and API URL adds clutter but does not obscure the core purpose.

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 offers no guidance on when to use this tool versus alternatives like weather_forecast or weather_history. It does not specify context, prerequisites, or exclusions.

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