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

Annotations already declare readOnly, idempotent and non-destructive, so the safety bar is pre-cleared. The description adds real domain context beyond that: pricing mirrors checkout ('the way checkout charges it'), the basket includes cleaning fee, taxes and refundable deposits, and it explicitly 'saves nothing and holds nothing.' It does not cover permissions or rate limits, but for a closed-world read-only quote the disclosure is solid.

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 scope, then detail, and short overall. A couple of the fragmentary noun-phrases ('for those dates in that number') are slightly elliptical, and enumerating the basket contents partially duplicates the existing output schema, 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 single complex nested parameter with full annotations and an output schema, the description covers the essentials: no persistence side effects, what the quote contains, and the charter tripType special case. Return-shape detail is not strictly required given the output schema, but the lack of any sibling-routing guidance leaves one small gap.

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?

The only top-level parameter (lines) is undocumented in the schema, and the description compensates by explaining that each line resolves to a price and a free/non-free status for the given dates and quantity. It also supplies a conditional routing hint the schema doesn't give: a fishing charter line takes tripType (half-day or full-day). The nested item fields are otherwise covered by the schema.

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 states a clear operation: it prices a whole basket of lines, the way checkout charges it, so an agent can distinguish it from price_cottages (which prices cottages only). The verb is implied rather than named outright ('quote/price'), and no sibling is named explicitly, but the multi-line 'whole basket' scope is 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?

There is no explicit 'use this when' and no alternative tool is named, so guidance is inferred rather than stated. 'Saves nothing and holds nothing' does signal this is a non-committing preview versus a booking tool like build_cart_link, which is a useful implicit usage cue, but the when-not conditions and siblings are left for the agent to infer.

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