Get detailed weather forecast for a specific location.

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

With no annotations provided, the description carries the full burden. It discloses the forecast includes temperature, wind conditions, and descriptions for 5 periods covering 2-3 days, which adds useful behavioral context beyond just 'retrieves forecast'. However, it doesn't mention rate limits, authentication needs, or error conditions.

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?

Two well-structured sentences with zero waste. The first establishes the core purpose and source, the second details the forecast content and temporal scope. Every element 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 tool has an output schema (so return values are documented elsewhere) and no annotations, the description provides good context about what data is retrieved and the temporal scope. It could be more complete by mentioning coordinate format or validation, but covers the essential purpose well.

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%, so the description must compensate. While it doesn't explicitly name the parameters, it specifies 'for the specified coordinates', which clearly implies latitude and longitude usage. This adds meaningful context beyond the bare schema, though it could be more explicit about parameter roles.

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 specific action ('Retrieves'), resource ('multi-period weather forecast'), and source ('from the National Weather Service'). It distinguishes this tool from siblings by specifying it provides detailed forecasts rather than alerts or general weather 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?

The description implies usage for detailed forecasts with coordinates, but doesn't explicitly state when to use this tool versus the 'get_weather' sibling. It provides context about what the forecast includes but lacks explicit guidance on alternatives or exclusions.

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