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

With no annotations provided, the description carries the full burden of disclosing behavior, but it only states the high-level outcome. It does not mention that the tool makes an external network call, that most of the nine input parameters are ignored, or what happens on failure or invalid input.

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 with no redundant wording. It states the core purpose and data source immediately, making it easy to parse.

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 nine parameters, no required fields, no output schema, and no annotations, the one-sentence description is insufficient. It omits the output format, unit of temperature, error behavior, and the fact that irrelevant parameters are ignored, so the agent does not have enough context to use the tool 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?

Although the schema already describes each parameter, the top-level description adds only the Open-Meteo source and does not clarify the relationship between the weather purpose and the many unrelated parameters. It fails to explain that only 'city' is semantically relevant while the other eight parameters appear to be discarded or used for unrelated checks.

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 identifies the tool's purpose: retrieving the current temperature for a city via Open-Meteo. It is distinguishable from sibling tools because no other sibling focuses on weather, though the lack of an explicit verb like 'gets' makes it slightly less direct.

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 does not mention use cases, prerequisites, or contrast with sibling tools, leaving the agent to infer when weather-hint is appropriate.

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