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

Annotations already cover the safety profile (readOnly, openWorld, idempotent, non-destructive), so the description doesn't need to restate that. It adds the 'current' temporal scope and Open-Meteo as the data source, but does not disclose output variables, units, or any service-specific behavior.

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 front-loaded sentence with no filler. Every word contributes to the meaning, and the structure is appropriately sized for a simple two-parameter weather lookup.

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 simple read-only query tool, the description is adequate but leaves some gaps: it does not describe return values (and there is no output schema), nor does it clarify coordinate parameter semantics. Annotations cover the safety context, so the main missing piece is expected response behavior.

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 schema provides 0% description coverage for parameters, and the description does not compensate by explaining latitude and longitude formats, coordinate order, units, or ranges. The property names are self-explanatory at a basic level, but the description adds no functional detail beyond 'specific location.'

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 a specific action ('Query'), a resource ('current weather conditions'), and a location qualifier. 'Open-Meteo' adds source context, making the tool's purpose obvious even among many query_* sibling tools, though it does not explicitly contrast with them.

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 this tool should be used when current weather conditions for a location are needed, but gives no explicit guidance about when not to use it or which sibling tool might be a better fit. With numerous query_* siblings, the intended use is inferable but not stated.

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