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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so safety is covered; the description adds real behavioral value by enumerating the specific metrics and the geographic scope (country-level aggregation, best/worst cities for the coming week). It stops short of noting rate limits, data freshness, or that results are forecast-based rather than historical, but the additions are substantive.

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 core concept (0-100 suitability score) is front-loaded, followed by the returned metrics and then routing/trigger guidance. The metric enumeration is long but each item earns its place by telling the agent what questions the tool answers; minor tightening would raise this to a 5.

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?

With an output schema present and rich annotations, the description needn't document return structure — and it doesn't. It covers scope, sibling routing, and example use cases, leaving only minor gaps (forecast horizon semantics beyond '7-day', data source/freshness) that are not essential to correct invocation.

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% — country_code is documented as ISO 3166-1 alpha-2 and locale as the display language — so the schema does the heavy lifting. The description only implies country-level input via 'Country-level' and adds no format or enumeration detail beyond the schema, warranting the baseline 3.

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 resource (country-level travel weather) and what the tool returns: a 0-100 travel/sleep score, solar yield, driving conditions, awning safety, condensation risk, 7-day forecast, and best/worst 3 cities. It explicitly contrasts with the sibling get_city_travel_weather, so an agent can distinguish the two without opening either schema.

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?

Names the alternative (get_city_travel_weather for a named city) and enumerates concrete triggering questions: what the weather is like in a country, where it is warmer/colder/sunnier, which cities are best/worst this week, whether it is too cold or rainy to sleep in a van. When-to-use and when-not-to-use are both explicit.

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