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

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so safety is covered. The description adds useful context beyond the annotations: payment status is driven by Stripe webhooks, guest_token is needed for guest purchases, and the tool does not update prior purchases. It stops short of explaining latency or return shape, but it meaningfully supplements the structured safety profile.

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?

The description is three compact sentences, front-loaded with the core purpose and followed by the two operationally relevant caveats. Every sentence carries useful information, and none are redundant with the annotations or schema.

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 read-only, two-parameter status tool with annotations present and no output schema, the description covers the essential context: what status is returned, the guest-token requirement, the webhook dependency, and the no-update behavior. It could be more complete if it described the returned status/tracking fields, but an agent has enough information to call the tool correctly.

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 50%: guest_token has a full schema description, while order_id is undocumented in the schema. The description adds the guest-only condition for guest_token but says nothing about order_id, so it partially compensates for the coverage gap without fully covering both parameters.

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 states a specific verb and resource: getting payment, fulfilment, and tracking status for a purchase. It scopes the resource to purchases created by the guest session or account connection, which implicitly separates it from cart-oriented siblings, but it does not explicitly name an alternative tool or draw a direct boundary with get_cart or checkout_session.

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 gives one conditional parameter instruction ('Supply guest_token for guest purchases') and notes that payment confirmation comes from Stripe webhooks, but it does not explain when to use this tool versus alternatives such as get_cart or checkout_session. There is no explicit when-not guidance, leaving the agent to infer the workflow position.

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