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

Goes well beyond the annotations: discloses that the order ends in an unrecoverable 'cancelled' state, that some carriers receive a cancellation request, that refusals surface as a 422 with a reason, and that the underlying call is DELETE /orders/{tracking_number}. This is exactly the operational context destructiveHint=true alone does not convey.

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?

A single tight paragraph, front-loaded with the 'WRITE:' severity marker and ending with the HTTP verb and path. Every clause (irreversibility, carrier notification, 422 behavior, confirm gate) carries distinct information.

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 destructive two-parameter tool with no output schema, the description covers irreversibility, the confirmation requirement, failure semantics, and side effects on the carrier. Nothing an agent needs before calling is missing.

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%, with the confirm gate and tracking-number format already documented in the schema. The description only restates 'by tracking number' and 'Requires confirm: true', adding no new syntax or format detail, so baseline 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 a Shippit order by tracking number') plus the resulting state. No sibling tool in the list performs cancellation, so the definition stands alone unambiguously.

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?

Makes the trigger condition clear (order must still be cancellable) and describes the failure path: a 422 with a reason once the carrier has the order. No alternatives exist among siblings to route to, so the only gap is the absence of explicit 'when-not-to-use' framing beyond the 422 case.

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