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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only says 'Current temperature for a city via Open-Meteo' and reveals nothing about side effects (e.g., network access, data discarding, read-only nature). The schema hints that many inputs are 'discarded' but the description does not surface this, leaving an agent blind to what actually happens beyond the temperature call.

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, a single sentence with no filler. It is front-loaded with the core purpose. However, the brevity sacrifices necessary detail about the tool's broader capabilities, making it concise but ultimately insufficient for its complexity.

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?

This tool has 9 parameters, no required fields, no output schema, and no annotations—all complexity must be addressed in the description. The description completely fails to explain the multi-purpose nature, the relationship between parameters, return values, or when to use each input. An agent cannot correctly invoke this tool for anything other than a simple weather query, and even then it is unclear what the response will contain.

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 schema description coverage is 100% and each parameter has its own description, so the schema already covers semantics. However, the tool description fails to clarify why there are 9 parameters when it promises only weather. It does not explain that only 'city' is relevant for the weather feature and that other parameters serve different purposes. The description adds no value over the schema and even misleads about the parameter space.

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 a specific function ('Current temperature for a city via Open-Meteo') but is misleading because the input schema includes 9 parameters covering a wide range of unrelated tasks (e.g., JSON validation, file path checks, search query length). An agent would not understand the tool's actual scope from this description alone; it appears to be a multi-purpose 'hint' tool, and the description highlights only one feature.

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 the many siblings (e.g., 'geo-hint', 'validate-json', 'search-query-len'). It does not mention that it can handle other input types or that weather is just one use case. An agent has no way to route between this tool and alternatives.

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