Create a fulfillment for an order

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

Annotations already declare destructive=true, idempotentHint=false and openWorldHint=true, so safety is covered. The description adds real value beyond that: a concrete rate limit (100 req/10s per shop) and the downstream side effects (order.status transitions through IN_PRODUCTION/PARTIALLY_SHIPPED/SHIPPED and order-updated webhooks fire). It does not say what a duplicate call does or what response is returned.

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?

Compact and front-loaded, with the rate limit placed first, then purpose, then state-transition behavior. Every sentence carries information and there is no filler.

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 an intricate payload/body-flag schema and no output schema, the description covers side effects and rate limiting well but leaves the parameter-shape ambiguity, confirmation semantics and error/repeat-call behavior undocumented. Adequate but with clear gaps for an agent to invoke it 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 coverage is only 57% and the description mentions only the concepts 'order items' and 'shipment tracker', adding no meaning beyond that. Critically, the schema exposes an ambiguous dual shape (top-level items/orderId/shippingLabel vs a nested payload object containing the same fields, plus payload_file, account and confirm), and the description does nothing to clarify which set to use or how confirm/account behave.

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+resource ('Creates a fulfillment') and adds the distinguishing detail that it attaches a shipment tracker for provided order items. No sibling tool covers fulfillment creation, so there is little to differentiate against, but the purpose is unambiguous.

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?

No guidance on when to create a fulfillment versus not, no prerequisites (e.g. order must be in a fulfillable state), and no mention of alternatives. The only contextual hint is the rate limit, which is operational rather than usage guidance.

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