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

Annotations only declare readOnlyHint=false, so the description carries most of the burden and does add real value: it discloses that this creates a binding real-world order and triggers a confirmation email to the customer, both side effects an agent cannot see from structured fields. It does not disclose whether the cart is emptied, whether the order can be cancelled afterward, or what errors occur on failure.

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, front-loaded with the highest-stakes information (real, binding order) followed by the confirm requirement and the customer-visible side effect. No filler or repetition.

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 high-stakes mutation with no output schema and sparse annotations, the description conveys the two things an agent most needs: the operation is irreversible/real and the customer is notified. The remaining gap is the undocumented non-required parameters, which is scored under parameter semantics rather than here.

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 only 40% across five parameters. The description only reinforces the confirm parameter (which the schema already explains in more detail) and says nothing about note, payment_method_id, delivery_method_id, or delivery_address_id, whose enum values (1,2,3 and 2..7) are completely opaque without descriptions. With low coverage the description was expected to compensate and does not.

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 ('Place a REAL, BINDING order from the current cart') and emphasizes the binding, non-preview nature, which implicitly separates it from checkout_preview. It stops short of naming the alternative tool, so an agent must infer the preview-vs-commit distinction rather than being routed explicitly.

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?

It states one hard precondition ('Requires confirm=true'), which is genuine usage guidance, and the schema reinforces that confirm should only be set after the customer approved the preview. However, there is no statement of when NOT to use this tool, no named alternative such as checkout_preview or add_to_cart, and no guidance on prerequisites like having items in the cart or a delivery address selected.

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