get_air_quality

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the agent knows this is a safe read operation. The description adds meaningful behavioral context: it retrieves current (not historical) data, requires a coordinate, and lists the specific data elements returned. It does not contradict annotations (annotation_contradiction=false).

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 two sentences: first sentence states purpose and outputs, second sentence adds a crucial prerequisite. Every sentence adds value, there is no redundancy or fluff, and it is front-loaded with the core function.

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 2-param tool with an existing output schema, the description covers purpose, output details, and a relevant prerequisite. It does not mention error conditions or rate limits, but the presence of the output schema reduces the need to explain return values. Slightly lacking in completeness for edge cases.

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 0% for both parameters, so the description must compensate. It mentions 'at a coordinate' but adds no further details about the latitude and longitude parameters (e.g., format, range, required constraints). For a low-coverage schema, this is insufficient compensation.

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 purpose with a specific verb and resource: 'Get current air quality at a coordinate'. It lists the specific outputs (local/universal AQI, dominant pollutant, concentration, health guidance), which distinguishes it from siblings like get_time_zone, get_elevation, and geocoding tools.

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 provides a clear usage prerequisite: 'Needs the Air Quality API enabled on the project, which is separate from the other Maps APIs.' This sets appropriate expectations. However, it does not explicitly compare this tool to siblings or give when-to-use/not-use guidance, though the context is clear from the purpose.

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