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

It adds real context beyond annotations: the result is bound to a specific revision, and 'Missing prices are unavailable, never zero' discloses failure semantics rather than silent zeroing. But annotations declare readOnlyHint=false and idempotentHint=false for what reads like a lookup, and the description never explains why the call is not read-only, whether it records anything, or why repeated calls could differ.

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 is returned, followed by scoping and error semantics. Each sentence contributes; the only weakness is that 'secure checkout' is a paraphrase rather than a concrete sibling reference.

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?

The description does say what the quote includes (print/postage/options) and what it excludes (tax, final total), which is useful given there is no output schema. It still leaves the return shape underspecified (currency, per-item breakdown) and says nothing about the required draft_id, which leaves gaps for a two-required-parameter call.

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 0%, so the description must carry the load. 'Revision-bound' hints that the version parameter selects which revision is priced, but neither parameter is explained: draft_id is never mentioned, and there is no guidance on what version numbering means or how stale versions behave.

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: 'Get a current revision-bound subtotal' of print/postage/options. It implicitly separates itself from the payment path by noting that tax and the final total come from secure checkout. It does not name sibling tools directly, so an agent must infer the boundary with checkout/prepare_checkout/quote_for_send.

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?

'Tax and full final total are shown by secure checkout before payment' implies this tool is for previewing the subtotal rather than completing payment. However, this routing is only implied, and the description never explicitly says when to call this tool rather than quote_for_send or prepare_checkout, nor does it state prerequisites.

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