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

With no annotations, the description carries the full burden of behavioral disclosure. It only states the core function and fails to mention that the other 8 parameters in the schema are discarded (as their descriptions indicate), that the tool is read-only, or what happens when the city is not found. This lack of transparency could mislead an agent into passing unrelated parameters expecting them to have effect.

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 short, but it is under-specified rather than concise. It omits critical information about the tool's scope and parameter handling. The single sentence does not earn its place because it fails to convey the tool's full behavior and leaves the agent to infer from the schema.

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's complexity (9 parameters, no annotations, no output schema), this description is grossly incomplete. It explains only one use case (city temperature) and provides no information about return format, error handling, or the purpose of the other parameters. An agent cannot reliably invoke this tool correctly based on the description alone.

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 baseline is 3. The tool description adds no extra meaning about parameters beyond what the schema already provides; it only implicitly mentions 'city' in the purpose. It neither clarifies nor contradicts the schema, so a 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 states a clear verb and resource: 'Current temperature for a city' with a specific data source (Open-Meteo). It is unambiguous about the core function but does not differentiate from siblings like geo-hint, which might also be location-related. No sibling comparison is given.

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?

No guidance is provided on when to use this tool versus alternatives. The description does not mention any exclusions, prerequisites, or conditions that would help an agent decide between weather-hint and other tools such as geo-hint or fetch-status.

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