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

The readOnlyHint annotation already indicates this is a safe read operation. The description adds no extra behavioral details (e.g., data source, update frequency, rate limits). It is adequate but does not go beyond annotation.

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 sentence with no wasted words. However, it achieves conciseness by omitting necessary details, which reduces usefulness. It is front-loaded with the key purpose but lacks structure for additional context.

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 no output schema and 3 parameters with no descriptions, the description is insufficient. It does not explain return structure, data availability, or spatial accuracy. For a tool with moderate complexity, it fails to provide a complete picture.

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?

With 0% schema description coverage, the description should explain parameters but does not. 'for a location' only vaguely implies lat/lon. The distance_miles parameter and its default are not mentioned. No unit or format guidance is given.

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 the tool's purpose: retrieving current air quality (AQI) for a location. The verb is implied by 'Current' and the resource is 'air quality (AQI)'. It is distinct from sibling tools like weather.current which provides meteorological data.

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 on when to use this tool versus alternatives. It does not specify prerequisites, such as valid lat/lon boundaries, or when not to use it (e.g., for forecasts). No comparison with similar tools like aqi.forecast if it existed.

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