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

There are no annotations, so the description carries the full burden. It conveys a read-only external lookup via Open-Meteo, which suggests no destructive side effects, but it does not disclose output format, units, failure modes, authentication needs, or rate limits. This is adequate for a simple public weather query but lacks detailed behavioral transparency.

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 only one sentence with no filler or redundant phrasing, and the key information is front-loaded. It is concise without being a tautology, though it may be slightly too terse given the schema's 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?

Given that there is no output schema and no annotations, the description should explain return format or units, and clarify which of the nine schema parameters are relevant. It only mentions city and ignores the rest of the schema, leaving the agent uncertain about the tool's actual inputs and output.

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 input schema has 100% parameter description coverage, including notes that many parameters are discarded. The description itself only references 'city' and adds no new parameter-level detail. Per the baseline for high schema coverage, a 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 states that the tool returns the current temperature for a city and names the data source (Open-Meteo). It is specific enough to distinguish from most sibling tools, though it does not explicitly name an alternative. The absence of a verb is a minor weakness, but the resource and action are unambiguous.

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 phrase 'for a city' implies that this tool should be used when a city's current temperature is needed, but it provides no explicit when-to-use or when-not-to-use guidance. It does not mention any alternative tools or exclusions, leaving the routing decision mostly to inference.

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