get_forecast

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

With no annotations, the description carries the burden of behavioral disclosure. It states the output is a 5-day forecast and supports city/coordinate input, but does not disclose unit defaults, precedence rules, or potential errors; the schema fills some gaps, so a 3 is a fair baseline.

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 12-word sentence that is entirely information-bearing, with no filler. It front-loads the action and outcome, making it maximally concise.

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?

The tool is simple enough that this one-sentence description plus a well-described schema is adequate. It does not explain return data structure, but an output schema is not present and the forecast format is likely conventional. Sibling differentiation is absent but not critical here.

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 input schema covers 100% of parameters with detailed descriptions including defaults and constraints, so the description adds little beyond naming the two lookup modes. The baseline of 3 is appropriate because the schema already does the heavy lifting.

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 returns a 5-day weather forecast using the verb 'get' and resource 'forecast', and specifies both the geographic scope ('any location worldwide') and input methods ('by city name or coordinates'). This distinguishes it from sibling tools like get_current_weather and get_alerts.

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 the tool is for multi-day forecasting, and the sibling names suggest alternatives for current conditions and alerts. However, it does not explicitly state when to prefer this tool over others or mention exclusions, so a 4 is appropriate.

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