cancel_delivery

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 genuinely new domain behavior: Drive cancellation rules apply and fees may still be due once a Dasher is assigned, plus the instruction to warn the user first — meaningful context the annotations do 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?

Two tight sentences, front-loaded with the action and followed by the caveat and the required user-facing step. No filler, though the parenthetical fee clause is slightly compressed.

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 destructive tool whose annotations cover safety and which has no output schema, the description supplies the key missing pieces: fee consequences and the user-warning obligation. It could still say what happens to an already-dispatched delivery or on repeated calls, but the essential context is present.

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% for the single required parameter external_delivery_id, so the description carries the burden of explaining it — and it says nothing about format, source, or where the ID comes from. The parameter name is somewhat self-explanatory, but the compensation the low coverage requires is absent.

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 delivery'), which is unambiguous against siblings like update_delivery and delete_install. It does not, however, explicitly distinguish itself from update_delivery, which could plausibly be used to cancel.

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?

Usage is implied (cancel a delivery the user no longer wants) and the description adds one precondition — tell the user before cancelling. It never states when to prefer this over update_delivery or what to do if cancellation is no longer possible.

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