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

Annotations already establish readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuinely useful behavior: 2-night Fri–Sun windows, ~8 vs ~6 weekend scope depending on mode, and results sorted cheapest-first. Rate limits and pricing freshness are not mentioned.

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, zero waste: the core action and the hotel_id/city branching are front-loaded, and no sentence merely restates the title or 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?

With no output schema, the description does enough by stating the result ordering and the volume of weekends covered. It could say more about what each priced weekend entry contains, but nothing needed to invoke the tool 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 baseline is 3, but the description adds real meaning beyond the schema: it explains the trade-off between hotel_id (one hotel, ~8 weekends) and city (Fostay curated stays, ~6 weekends). That is more than the schema's terse 'used when hotel_id is omitted'.

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 (prices) and resource (upcoming Fri–Sun weekends) plus the goal (find cheapest times to stay), which no sibling like get_live_rates or demand_calendar claims. An agent can tell this is a flexible-date price scan rather than a single-date lookup.

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 describes the two invocation modes: pass hotel_id for one property across ~8 weekends, or a city to compare curated stays across ~6 weekends. It does not name or exclude alternative sibling tools for other date-range questions, so it stops short of full when/when-not guidance.

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