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

Annotations already declare destructiveHint=true and idempotentHint=false, so the safety profile is covered. The description adds genuine financial context not present in the annotations: no charge occurs and the card authorisation is released. It omits what happens on a second call (non-idempotent) or on an already-delivered order.

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 with zero filler; the actor and precondition lead, and the financial consequence follows. Every clause earns its place.

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 single-parameter mutation with no output schema, the description covers actor, precondition, and financial effect, and annotations cover destruction/non-idempotency. The remaining gap is the order_id source and error behavior, which are minor but real.

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 0% and there is a single required order_id, whose format/source (e.g. from my_orders or get_order) the description never explains. The phrase 'an order' only loosely implies what order_id should be, so it adds minimal meaning over the schema.

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 and resource ('cancel an order') plus the actor ('Buyer') and the qualifying condition ('not delivered'), so an agent can distinguish it from get_order, my_orders, or redeliver without opening any schema.

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?

Gives clear when-to-use context (buyer, undelivered order), which implicitly excludes delivered orders. It does not name an alternative path for delivered orders or state what to do if cancellation is unavailable, so it stops short of explicit when-not guidance.

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