weather_forecast

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

With no annotations, the description carries the full burden and does reasonably well: it discloses the upstream data source (Open-Meteo), the sampling points (departure/high point/arrival), the forecast horizon limit (15 jours), and the default behavior when date/time are omitted (fallback to set_constraints, 9 h departure). It does not cover failure modes or behavior beyond the horizon, so not a 5.

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?

Three compact sentences, front-loaded with the purpose, then output scope, then defaults. Dense but no filler; every clause carries information. Could be marginally tighter but well structured.

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 read-only forecast query with an output schema (so return values need no prose), the description covers data source, variables, time points, horizon, and default inputs. The absence of any handling/limit caveats beyond '15 days' is the only real gap.

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. It explains the semantics of two of three params by defining what happens when date/start_time are absent (use set_constraints values, 9 h default) – adding meaning beyond the schema's bare null defaults. route_id is left implicit but is self-evident from the name.

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?

States a specific verb+resource: fetching Open-Meteo weather forecasts for a route, itemizing exactly which time points (départ, point culminant, arrivée) and which variables (températures, pluie, rafales, orage, neige au sol) are returned. No sibling tool overlaps with weather, so the agent can identify it immediately.

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?

Usage is implied rather than stated – there is no explicit 'when to use this vs alternatives' guidance (though no sibling provides weather). The only operational guidance is the fallback rule ('Utilise la date/heure de set_constraints si elles ne sont pas fournies'), which gives context but is really a behavioral default, not a selection rule.

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