Weather – 48-Hour Forecast

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

With no annotations provided, the description carries the full behavioral disclosure burden. It discloses the maximum number of records ('up to 48 hourly records'), the no-data case ('or no data if none is available'), and the full set of returned fields. This is substantial transparency for a read-only forecast tool.

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 with no filler. The first sentence front-loads the core action and data scope, and the second covers the edge case of no available data. Every sentence earns its place.

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 absence of an output schema, the description does a good job enumerating what the response contains and its limits. Combined with the fully documented input schema and clear divergence from sibling tools, an agent has enough to select and invoke the tool correctly. Minor gaps like exact response shape or timezone handling are not critical for this forecast tool.

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 schema already explains every parameter, including lat/lng/place mutual requirements and the units enum. The tool description adds no parameter-level detail, but the baseline of 3 is appropriate when the schema fully documents parameters.

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 specific verb ('Returns') and resource ('hourly weather forecast for the next 48 hours') and enumerates the returned fields. This clearly differentiates it from sibling tools like weather_latest, air_quality_forecast, and pollen_forecast.

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 establishes clear usage context: it is for the next 48 hours at hourly granularity, which distinguishes it from weather_latest and air quality/pollen tools. It does not explicitly name alternatives or state when not to use it, but the temporal and domain framing makes the intended use clear.

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