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

Annotations already flag destructive=true and idempotent=true, and the description goes beyond them with concrete consequences: removal from public search, irreversibility through this tool, and the seller-approval gate. 'Already-cancelled retries succeed' restates idempotentHint, but the effect and irreversibility disclosures add genuine behavioral value.

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?

Four tight sentences front-load the precondition and the credential requirement before the effects and reversibility caveat. Every sentence carries a distinct fact with no filler.

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, no-output-schema mutation, the description covers preconditions, required auth, side effects, idempotency, and irreversibility. It omits what response or error surfaces on a stale expected_updated_at conflict, which is the one remaining gap an agent would benefit from.

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 a mid-range 67%: management_token and expected_updated_at are documented in the schema, while slug has no description anywhere. The description echoes two of the three required params ('management token', 'latest updated_at') but adds no format or syntax detail, so it only marginally exceeds the schema baseline.

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?

The description opens with a specific verb+resource ('Cancel a listing') and immediately scopes it ('only after explicit seller approval'), which is unambiguous against siblings like prepare_sale, publish_sale, or update_sale. The added note that cancellation cannot be reversed through this tool further separates it from the update path.

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?

It states a real precondition ('only after explicit seller approval') and the required credentials ('its private management token and latest updated_at'), plus retry behavior for repeat calls. It does not name an alternative tool (e.g., use update_sale to modify instead of cancel), so the when-not guidance is implied rather than explicit.

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