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

Adds substantial information beyond the annotations: the call is non-committing, returns a preview of changes plus a confirmation link, and requires merchant action to take effect. It also states the money unit convention (integer minor units/cents), which prevents a costly misinterpretation of monetary fields. This explains why readOnlyHint=false despite 'changes nothing' — the call still produces preview state and a link.

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?

Four short sentences, all load-bearing, with the most surprising fact (the call is a preview) placed early. No filler or restatement of the tool name beyond the opening clause.

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 complex nested-payload tool with no output schema, the description covers the ruling behavioral constraint (nothing is committed until the merchant confirms) and the money convention. It leaves the required-payload composition to the schema's nested descriptions, which are reasonably rich, but does not summarize what a successful call returns beyond 'a preview and a confirmation link'.

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?

With schema description coverage at only 33% and six parameters including nested customer/lines/discount/shipping objects, the description contributes only the global cents convention and nothing about required pairs (customer, lines) or how product/variant/sku resolution works. The nested schema descriptions do carry much of the load, so this is a baseline-adequate rather than compensating description.

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 ('Create an order') and then immediately reframes what creation actually means here: a preview plus confirmation link, not a committed write. It also names the downstream siblings (orders_send_payment_link, orders_mark_paid) so the agent can place it in the order lifecycle.

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?

Clearly explains the intended context: the agent prepares an order, and only the merchant on the returned page can finalize it, which tells the agent not to expect a created order back. It does not explicitly say when to prefer this over siblings like orders_lookup or customers_create, though those are covered in the schema description.

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