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

Annotations already cover the safety profile (readOnlyHint, openWorldHint), and the description adds genuinely non-derivable behavior: the quote is fresh, itemized and all-in, and the returned quote_id expires after 15 minutes. It omits what happens on an unavailable or failed quote and whether price can shift mid-flow, which keeps it off 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?

Two sentences, no filler, with the return value and the critical 15-minute validity window front-loaded in the same line. Every clause carries operational information.

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 description does the work of naming the return payload (itemized all-in price, availability, quote_id) and its TTL, which is enough to call and consume it. Minor gaps remain around failure modes and whether the quote must be re-fetched if booking later than the validity window.

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 seven parameters including the guest-breakdown fields are already documented. The description only adds that the call is scoped to one offer_id and a specific date/guest combination; baseline 3 is appropriate.

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 and resource ('Gets a fresh, itemized all-in price and availability') for one offer_id, and names the two sibling tools that produce that offer_id, so the agent can distinguish it from search_stays and find_cheaper without opening a 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?

Pins the input provenance (offer_id from find_cheaper or search_stays) and the downstream consumer ('a quote_id that book needs'), which effectively describes the quote-then-book pipeline. It stops short of explicit exclusions, e.g. that a quote is not needed when re-searching or that stale quotes must be re-fetched rather than reused.

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