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

Annotations only supply readOnlyHint and openWorldHint; the description goes well beyond them by enumerating the full status lifecycle and what each implies. It discloses genuinely useful behavior: nothing is charged before ID approval, refunds are possible during activating and before delivery, and delivered orders expose eSIM activation details or proxy lines.

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 return shape are front-loaded in the first clause, with the status glossary following. The status enumeration is long but dense with operative meaning rather than padding; slight compression of the pending_payment and activating parentheticals would help, but nothing is wasted.

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?

There is no output schema, so the description carries the return contract alone and does so: cart status, per-item status_url, and the activation payloads that appear at delivered. Combined with the status glossary, an agent has enough to interpret every response state without further documentation.

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 both parameters are already documented, including the XC- prefix and the status_token's origin in create_cart_order. The description adds no format, validation, or failure-mode detail for either parameter, so the baseline of 3 applies.

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 opens with a specific verb and resource ('Look up a cart made with create_cart_order') and states exactly what comes back: the cart status plus each item with its own status_url. It implicitly separates itself from get_order_status by anchoring the lookup to create_cart_order, though it never names the order-status alternative outright.

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 context is clear: this is the read-side companion to create_cart_order, so an agent knows to call it after creating a cart. It adds situational guidance for the pending_payment case (phone-number orders held for ID check, payment_url appearing on approval), but gives no explicit when-not-to-use or direction to get_order_status for non-cart references.

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