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

Goes well beyond the annotations by disclosing the tool's real effect: it performs no change itself, it returns a preview of the diff plus a confirmation link, and only the merchant acting on that page can apply it. It also documents the destructive edge case ('orders already taken keep their answers') inside the action parameter. The one caveat is that 'Calling this changes nothing' sits in mild tension with readOnlyHint=false, though a staged proposal plausibly justifies the write hint.

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?

Purpose and preview semantics are front-loaded and well ordered. However, the sentence 'Money is integer minor units (cents)' is irrelevant to this tool, which has no money parameter, and it wastes attention and could mislead an agent into expecting a price field.

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 six parameters, no output schema, and no annotation detail, the description successfully fills the biggest gap by describing the return value (preview plus confirmation link). Minor omission: it does not say what happens when 'set' is called on a label that does not exist yet versus one that does, beyond what the schema already states.

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%, so the description carries no burden here and adds nothing beyond the schema. Baseline of 3 is appropriate; the label matching rule, enum meanings, and removal semantics are all already in 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?

Names a specific verb+resource: asking buyers a custom question at checkout. An agent immediately understands the capability. It does not distinguish itself from the adjacent settings_checkout and settings_checkout_extras siblings, so an agent has no text-level cue about which of the three to pick.

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?

Usage is only implied by the phrasing 'ask buyers a question of your own at checkout'. There is no explicit when-to-use, no when-not-to-use, and no pointer to settings_checkout or settings_checkout_extras as alternatives for related checkout configuration.

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