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

Annotations already declare destructiveHint=true and idempotentHint=true, so the safety profile is covered. The description adds real value beyond that: the production-state precondition, the concrete failure mode (HTTP 409), and explicit irreversibility ("cannot be undone"). It does not describe the response payload, but with annotations carrying the safety semantics this is solid coverage.

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?

Three short sentences: action, failure precondition, irreversibility. The most decision-relevant fact (must be before production) is front-loaded and 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?

For a single-parameter mutation with no output schema, the description covers the key decision inputs: timing window, failure behavior, and irreversibility. Only the exhausted-state note (what happens to an already-cancelled order, given idempotentHint) is left unaddressed.

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 100% for the single order_id parameter, so the schema already documents the input fully. The description adds no parameter-level detail (no id format, source of the id, or overrides) beyond the endpoint path, 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?

States a specific verb and resource ("Cancel an order") and adds the scope constraint "before production," which separates it from siblings like gelato_delete_draft_order and gelato_create_order. An agent can identify the operation without opening the 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 a clear precondition for use (before production) and the exact condition under which the call fails (HTTP 409 once any item is printed or shipped). It does not explicitly name an alternative tool or say when another sibling should be preferred, so it falls short of a full when/when-not mapping.

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