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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered; the description adds genuinely new behavior: it 'returns data only', must be followed by render_destination_info to surface the card, and is not for bookings. These workflow constraints go well beyond what the structured fields convey.

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?

It is front-loaded with the core purpose and every clause routes the agent somewhere useful, but the weather/climate exclusion runs to two dense sentences and could be tightened without losing meaning. No filler, though – all content is operational.

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?

An output schema exists, so return values need no explanation, and the description still covers the required follow-up render call, the input prerequisite, and the scope boundary against weather and booking siblings. Nothing an agent needs to invoke this correctly is missing.

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% and the handle format is already documented in the schema ('Sorted sitemap handle such as paris, hanoi, or tokyo'). The description's handle examples and the resolve_destination fallback add modest routing value but no new argument semantics, so the baseline 3 applies.

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 opening sentence gives a specific verb and resource ('Get Sorted on-the-ground facts for one destination handle') and enumerates the payload (brief, safety, currency, phone code, eSIM notes, taxi apps). It explicitly separates itself from get_destination_weather and resolve_destination, so an agent can pick it without opening any 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?

It names this as the default for generic info asks with example utterances, states the prerequisite (call resolve_destination first if you only have a name), and gives a concrete exclusion ('Use get_destination_weather only when the traveler explicitly asks for current weather, a 7-day forecast...'). When-to-use, when-not-to-use, and the alternative are all present.

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