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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint false, so the safety profile is covered. The description adds the data-provenance dependency (both arguments must come from a prior search_hotels call) and the routing constraint on booking links, but no rate limits, caching, or failure modes. Since an output schema exists and annotations handle safety, this is a genuine but modest addition.

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?

Three tight sentences, front-loaded with the trigger condition before the alternatives and prerequisites. The mid-sentence enumeration of returned fields is slightly list-heavy but every item is differentiating information, not filler.

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 prose, annotations cover the safety profile, and the description covers trigger, prerequisites, and the two adjacent siblings. Nothing an agent needs to call 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 both param descriptions already say 'from search_hotels', so the description's 'Takes the search_key and hotel_id from search_hotels' largely repeats the schema. It adds the useful implicit constraint that these are search-scoped, not global IDs, but no format or validity details. 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?

Names a specific verb+resource (fetch details/photos/rooms/rating for ONE hotel) and enumerates the payload returned, so the agent knows exactly what it gets. It explicitly distinguishes itself from hotel_price_calendar (prices across dates) and hotel_booking_options (links).

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?

States the trigger condition ('traveler asks for details, more information, photos, rooms or description of one hotel'), the alternative to use for dates/prices, and the sibling for booking links with a gating condition ('call that only when they say book'). Prerequisites for both params are given.

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