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

With no annotations, the description bears full responsibility for behavioral disclosure. It only states the basic function, but does not disclose that most of the 9 parameters are discarded, nor does it mention any side effects, rate limits, or output structure. The schema descriptions partially cover parameter behavior, but the description adds no extra context.

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 a single concise sentence, front-loading the essential purpose. It is not bloated and is easy to read. However, its brevity borders on under-specification given the complex schema, but as a concise statement it is acceptable.

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 9 optional parameters and no output schema or annotations, the description is incomplete. It does not explain that only 'city' matters, what the return value looks like, or any constraints (e.g., city name format, Open-Meteo limitations). An agent calling this tool would lack critical information to use it correctly.

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?

Schema coverage is 100%, so baseline is 3. The description does not add any nuance beyond the schema's per-parameter descriptions. It mentions 'city' but the schema already describes it. The description does not clarify that only city is used or explain the role of other parameters, so it adds no value beyond the schema.

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 a specific action and resource: retrieving current temperature for a city via Open-Meteo. However, it does not differentiate from sibling tools like geo-hint or timezone, and the large parameter list introduces ambiguity about what the tool actually accomplishes. The core purpose is understandable but not fully clarified in relation to its schema.

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?

No guidance is given on when to use this tool versus alternatives. The description does not mention that only the 'city' parameter is relevant or that other parameters are ignored, leaving the agent without direction on how to call it appropriately. There is no mention of when not to use it.

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