Cancel a sale before dispatch (seller)

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

Annotations already flag destructiveHint=true, and the description adds the consequences that matter: buyer refunded in full immediately, reason text is visible to the buyer, no reputation penalty, and the API key requirement. It also explains the relist side-effect on the listing, which the annotations alone would 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?

Role and state precondition are front-loaded and every clause carries information, but the middle section is dense with em-dash asides that take a second pass to parse. Slightly tighter grouping of the refund/relist/reputation facts would help.

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 mutation with no output schema, the description covers the refund outcome, the listing side-effect, the reputation consequence, the visibility of the reason, and the auth requirement — everything needed to call it safely and predict the result.

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%, so the baseline is 3, but the description goes further by explaining the branch between 'relist: true puts the listing straight back on the market' and the deferred relist_listing path, and by warning that the reason string is buyer-visible. Only the transaction_id parameter is left to 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 ('call off a sale') plus the exact lifecycle state required ('escrow_held (not yet dispatched)'), which cleanly separates it from sibling tools like delist_listing and relist_listing. An agent can identify the operation and its precondition 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 an explicit when ('state escrow_held (not yet dispatched)'), a when-not ('only cancel when you genuinely can't ship'), and a concrete alternative for the adjacent case ('otherwise relist later with relist_listing'). Routing between this tool and relist_listing/delist_listing is fully determined.

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