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

There are no annotations, so the description carries the full burden of explaining behavior. It says 'via Open-Meteo', which suggests an external call, but it does not disclose failure behavior, rate limits, response shape, or what 'discarded after the call' means for the city parameter. The behavioral context is minimal.

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 short sentence with no wasted words, so it is concise. However, for a tool with nine parameters and no annotations, this brevity is under-specification rather than effective compression. It front-loads the core idea but omits context needed for correct invocation.

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?

With no annotations, no output schema, and nine parameters, the description is far too thin to give an agent complete guidance. It does not explain which of the nine optional parameters to provide, why so many unrelated parameters exist, what the response looks like, or whether an external network call is required. The agent is left to guess the intended call shape.

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 description coverage is 100%, so the schema already documents each parameter. The description adds only that 'city' is the relevant input, while the schema itself describes the other eight parameters as mostly discarded or irrelevant. This leaves the tool's actual parameter selection ambiguous, so the description does not meaningfully improve parameter understanding beyond the schema baseline.

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 the tool returns current temperature for a city and names the data source (Open-Meteo), making the core purpose reasonably clear. It is not a tautology and is more specific than the bare name. However, it does not distinguish itself from the sibling 'geo-hint' tool, which could plausibly overlap.

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 implies the tool is for city-based weather lookups but gives no explicit guidance on when to choose it over alternatives like 'geo-hint' or 'web-fetch'. There are no stated exclusions, prerequisites, or conditions that would help an agent route to this tool reliably.

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