Search hotels

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

Annotations already declare readOnly/idempotent/non-destructive/openWorld, so the safety profile is covered. The description goes beyond them by disclosing that sold-out hotels are excluded, that guest count does not affect prices, and how the returned price fields relate to each other. It does not mention pagination behavior despite the limit parameter, so it stops short of 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?

Front-loaded with the core purpose, then dense but purposeful sentences that each add routing or semantics. The telegraphic style ('Next: mb_hotel (reviews, location)') is efficient but sacrifices some readability, keeping it just short of a 5.

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?

For a 9-parameter search tool with an output schema, annotations, and many siblings, the description covers exclusions, price interpretation, guest-count behavior, and next-step tools. Nothing an agent needs to call it 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 coverage is 100%, so the baseline is 3. The description adds real meaning beyond the schema by clarifying price semantics (cheapest room for all nights vs. per-night, after discount) and that guest count is not a pricing input, which is non-obvious and affects how the agent should combine this with mb_hotel_rooms.

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 ('Hotels and stays with a free room in a city for the dates, with the cheapest room price for the whole stay'), including the scope constraint that only hotels with availability are returned. It explicitly contrasts itself with siblings (mb_city_hotels lists every hotel; mb_hotel_rooms gives exact prices), so an agent can distinguish it without opening another 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?

Explicitly routes the agent: use mb_hotel_rooms(guests=...) to pick a room that fits, mb_hotel for reviews/location, mb_hotel_calendar for cheapest nights, and mb_city_hotels when sold-out properties matter. It also states the condition under which this tool omits results, which is exactly the when-not guidance needed.

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