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

Annotations already flag destructiveHint/readOnlyHint=false, but the description goes well beyond them: it discloses irreversibility ('Cannot be undone'), the carrier cut-off window that determines success or failure, the confirm-after-agreement protocol, and the underlying DELETE endpoint. This is the kind of behavioral context an agent needs before firing an irreversible write.

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?

Front-loads the WRITE/DESTRUCTIVE warning, then the branching success condition, then the irreversibility and confirmation requirement, then the endpoint. No filler sentences; every clause carries decision-relevant 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 two-parameter destructive tool with no output schema, the description covers safety profile, success/failure conditions, precondition for invocation, and reversibility. Nothing an agent needs in order to call it correctly 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 description coverage is 100% and the confirm parameter is already documented in detail inline, including 'Set it ONLY after the user has explicitly agreed.' The description's line about confirm=true largely restates the schema; it adds only the linkage that the confirmation also covers label cancellation. Baseline 3 is appropriate when the schema carries the semantics.

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 ('delete a shipment') and immediately distinguishes the two cases that matter: a prepared shipment with no label versus one already carrying a label whose cancellation is time-bounded. An agent can tell exactly what this does versus siblings like shipcloud_get_shipment or shipcloud_create_shipment_with_label.

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 an explicit when-it-works / when-it-fails rule (prepared shipments any time; labeled shipments only before the carrier cut-off of roughly 17:00-20:00), plus a hard precondition that the user must have agreed before confirm=true. It does not name sibling tools for checking shipment status first, so the routing guidance is context-rich but not comparative.

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