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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, covering safety and idempotency. The description adds the 93-day date range limit and that it returns open/blocked nights and minimum stay, which are behavioral details beyond the annotations. It does not describe the response format or error handling, but for a read-only calendar query, the added context is meaningful and raises it above baseline.

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?

The description is two sentences, front-loaded with the primary purpose (open and blocked nights for one property over a date range up to 93 days, with minimum stay) and then gives usage guidance. Every word earns its place; there is no redundancy or fluff.

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 simple read-only query with three well-documented parameters, the description covers the purpose, the output (open/blocked nights, minimum stay), the date range limit, and usage guidance. Annotations cover safety and idempotency, and there is no output schema requiring explanation. The tool is fully specified for an agent to call it correctly.

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%, with each parameter (property_id, start_date, end_date) having a clear description. The tool description does not add parameter-specific syntax or details beyond what the schema already provides. According to the rubric, when schema coverage is high, a baseline of 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?

The description clearly states the tool retrieves open and blocked nights for one property over a date range, including the minimum stay. It explicitly differentiates from get_live_quote by noting that this tool is for suggesting alternative dates, while get_live_quote confirms and prices a specific stay. This provides a specific verb, resource, and scope, and distinguishes it from a key sibling.

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?

The description gives explicit usage guidance: 'Use this to suggest alternative dates; use get_live_quote to confirm and price a specific stay.' This tells the agent when to select this tool versus the sibling get_live_quote, leaving no ambiguity about the tool's role.

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