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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent write; the description adds real value beyond them by naming the credential requirement and the specific 403 failure mode for unclaimed sandbox workspaces. It still doesn't say whether repeated calls duplicate orders or what is returned on success.

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 the action and its fields, followed by two short prerequisite sentences. Dense but every clause carries information; the only mildly awkward part is packing all field defaults into one long sentence.

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 7-parameter mutation with no output schema and full schema coverage, the description covers the fields, defaults, and the authentication/workspace gates. It leaves out the success response shape and duplicate-handling behavior, which are the main remaining gaps.

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 100%, so a 3 is the baseline, but the description goes further: it states defaults the schema omits (status defaults to draft, total_amount defaults to 0) and constrains billing_contact_id as "a contact of that customer." That is genuine semantic enrichment beyond the parameter descriptions.

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?

"Add an order for a customer" gives a specific verb and resource, and enumerates the fields that can be set, so an agent can tell it apart from list_orders, update_order, or add_order_line. It stops short of explicitly naming the sibling used for line items, so differentiation is inferred rather than stated.

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?

The description implies the usage context (create a new order record) and supplies prerequisites, but never states when to prefer this over create_invoice, sync_commerce_orders, or when an order should instead be built via add_order_line. No explicit exclusions or alternatives are given.

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