get_hourly_forecast

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

With no annotations, the description carries the full burden. It discloses key behaviors: the data source (AROME/C-LAEF), forecast horizon (up to ~60 h), hours clamping (1–60), and the start parameter semantics ('begins at/after this instant'). It also warns about out-of-coverage responses. It doesn't mention auth, rate limits, or side effects, but for a read-only forecast tool these are less critical; the provided behavioral details exceed what a title/schema alone would offer.

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 well-structured: a one-sentence purpose, a brief context sentence with data source and coverage, a note on out-of-coverage behavior, and a clearly separated Args section. It is concise enough for a 4-parameter tool, and every sentence contributes either purpose, constraints, or parameter semantics. No filler or redundancy.

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 moderately complex with 4 parameters and an output schema. The description covers all necessary aspects: what it does, where it works, parameter details, and edge-case behavior (out-of-coverage). Since an output schema exists, the description doesn't need to explain return values. The coverage is complete for an agent to select and invoke it correctly.

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 fully explain parameters. It does: latitude/longitude with a concrete example, hours with default and clamp range, and start with an ISO 8601 example and behavior ('forecast begins at/after this instant'). Every parameter in the schema is accounted for, and the description adds meaningful constraints and formats beyond the bare type definitions.

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 opens with a specific verb+resource: 'Get an hour-by-hour weather forecast for a location.' This clearly distinguishes it from sibling tools like get_current_weather (current conditions) and get_storm_outlook (storm alerts). The mention of 'hour-by-hour' and 'forecast' makes the tool's unique scope obvious.

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 states clear usage context: it serves Austria and the Alpine region only, and explicitly notes that a point outside the grid returns an out-of-coverage notice. It also instructs the agent to geocode city names to coordinates itself, implying a prerequisite. It does not name alternative tools explicitly, but the geographic constraint and hour-by-hour nature create clear usage boundaries.

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