Hotel price calendar

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

Annotations already cover safety (readOnly, idempotent, non-destructive), yet the description adds the domain semantics an agent actually needs: missing nights mean no free room, and nights past the last entry mean 'not loaded yet' rather than sold out. That is exactly the kind of non-obvious behavior annotations cannot express.

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 short sentences, front-loaded with what the tool returns and its range, followed by usage routing and the edge-case semantics. No filler or restatement of the name.

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 formatting needn't be explained, and the description covers the remaining gaps an agent would hit: the range limit, gaps meaning no availability, and truncation meaning unloaded rather than sold out. Nothing needed 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 description coverage is 100%, and the schema itself documents the 'city_slug/hotel_slug' format with an example and regex. The description adds nothing about the parameter, so the 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?

States a specific verb and resource ('cheapest one-night room price per night') plus an explicit scope ('from today, up to about 48 days'). The 'hotel' framing plus the sibling set (bus/flight/train calendars) makes the domain unambiguous.

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 says when to use it ('find the cheapest or the next free nights') and routes the agent to the follow-up tool ('then mb_hotel_rooms for exact prices'). The distinction between the calendar (cheapest/availability overview) and the rooms tool (exact prices) is spelled out, not inferred.

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