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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false, so safety is covered; the description adds real value on top by asserting 'Nothing is generated' and naming the upstream data source (existing route ideas on wemake.holiday) and the output composition. It also discloses the graceful-failure behavior, which is exactly the kind of trait annotations cannot express. It stops short of describing latency, data freshness, or what happens when multiple route ideas match.

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?

Two sentences, no filler, with the core purpose front-loaded before the non-generative constraint and fallback. The parenthetical listing stations/nights/best months is compact and earns its space by defining the plan's contents.

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 covers source data, scope, and the empty-result path for a moderately complex composition tool. The only minor gap is the relationship to the sibling lookup tools when route ideas do exist — whether to inspect them first or call this directly.

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%, so all four parameters (country, days, topic, language) are already documented, including the 'closest existing route is chosen' behavior for days. The description reinforces that country/topic drive route-idea lookup but adds no syntax, format, or edge-case detail beyond the schema. Baseline 3 is appropriate when the schema carries the parameter burden.

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 ('put together a trip plan') and resource (a country's existing route ideas plus bookable experiences per station), and explicitly clarifies what the output is composed of (stations, nights, best months). This distinguishes it from siblings like list_route_ideas and get_route_idea, which surface raw ideas rather than an assembled plan.

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?

Gives a clear negative condition: if no route idea exists for the country/topic, say so and offer search_hotels or search_experiences instead. That is an explicit fallback path with named alternatives. It does not, however, state when an agent should call this versus first calling list_route_ideas/get_route_idea to inspect ideas, leaving that ordering to inference.

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