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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions the data source (Open-Meteo) but not what the tool returns, whether it makes a network request, or that most schema parameters are discarded after a shape check. The schema descriptions reveal this discarded-parameter behavior, but the main description fails to communicate it to the agent.

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, efficient sentence with no filler or repetition. It front-loads the purpose and provider. However, it is so terse that it omits important behavioral context, so it earns a high conciseness score but not a perfect one.

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?

For a tool with 9 parameters, no output schema, no annotations, and a schema containing many seemingly unrelated fields, the description is insufficiently complete. It does not clarify which parameters are actually used, what the output looks like, or why fields like 'ref', 'feed', and 'host' are present. An agent could be confused about whether those fields influence the weather result.

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 each parameter already has a documented meaning, including the 'discarded after' behavior. The description adds minimal value beyond identifying 'city' as the relevant weather parameter. Given the high schema coverage, a baseline of 3 is appropriate; the description does not need to repeat parameter details.

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 the tool's core function: returning the current temperature for a city via Open-Meteo. It uses a specific resource (city weather) and provider, which distinguishes it from sibling tools like geo-hint. However, it does not explain that several input schema fields are intentionally discarded as 'hints' unrelated to weather.

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?

There is no guidance about when to use this tool versus alternatives, nor any mention of prerequisites or exclusions. The description implies it should be used for current city temperature, but it never states a decision rule or names sibling tools for comparison. This is essentially no usage guidance beyond the bare purpose.

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