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

Annotations already establish the safe-read profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description nonetheless adds real domain behavior: the calendar carries a 48-hour turnaround buffer, and the tool will not book or hold. That buffer detail is exactly the kind of non-obvious trait that changes how an agent interprets results.

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 short sentences, no filler, and the core capability is stated first with the exclusionary caveat second. Nothing could be removed without losing information.

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?

No output schema is present, so the description ideally would hint at what the calendar returns (which dates, how the 48-hour buffer appears in the response), and the two required parameters are left entirely unexplained. It is adequate for a simple read tool but incomplete on the return shape and input meanings.

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 0% and the description never mentions 'start' or 'nights'. It does not explain the date format, that nights is a count of nights (max 90), or whether the buffer is applied to the whole range. With two required, undocumented parameters, this is a clear gap.

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 gives a specific verb and resource: 'Read Dream On's official unavailable-date calendar.' That is unambiguous, and the second sentence's clarification that it neither books nor holds dates further pins down what the tool is. It does not explicitly contrast itself with the sibling tools (get_yacht, list_yachts), so it stops short of a 5.

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?

'This does not book or hold dates; refer guests to dreamonsail.com' is explicit negative guidance and routes the user to the correct alternative channel for booking. What's missing is a positive statement of the situation that selects this tool (e.g., 'use before quoting dates to a guest').

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