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

Annotations already establish read-only, idempotent, closed-world behavior, so the description wisely spends its words on data semantics instead: day indexing (Day 0 is Friday), the pricing tier behind cost_cents, and that reserve_days is null for soft steps. It omits what happens when no published itinerary exists for the pair, which is the main remaining behavioral gap.

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?

A single front-loaded sentence that leads with what the tool returns and then enumerates fields without filler. It is dense but every clause carries information; a short second sentence on the not-found case would have been worth the tokens.

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 no output schema, the field inventory (days, steps, local times, kind, notes, cost_cents, reserve_days, fallback, venue with coordinates and offers) is exactly the right content and makes the return shape predictable. Missing only error/empty-case behavior and confirmation of whether lang affects the returned field names.

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 coverage is 100% for all three parameters, so baseline is 3. The description reinforces that city and persona are a paired key but adds nothing about lang, whose i18n-collapsing behavior is documented only in the schema.

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 the resource precisely ('the full published itinerary for one (city, persona)') and the keying, which separates it from list_published_itineraries and the estimate tools. It does not name a verb or explicitly contrast with siblings, so it stops short of a 5.

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?

There is no statement of when to use this tool versus list_published_itineraries, estimate_itinerary, or itinerary_calendar. The keying by (city, persona) implies it is the detail view of a listed itinerary, but the agent must infer that from the sibling names.

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