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

No annotations are provided, so the description carries the full behavioral burden. 'Unsigned transaction payload' and 'requires seller wallet signature' make clear that the tool does not directly perform the cancellation and that external signing is needed. It could mention ownership validation or error conditions, but the core side-effect profile is fairly transparent.

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?

The description is two compact sentences with no filler. The primary action is front-loaded, and the essential prerequisite about seller signature is placed immediately after.

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?

Both required parameters are fully documented in the schema, and the description states the return outcome ('unsigned transaction payload') and a key prerequisite. It omits edge cases or failure reasons, but for tool selection and basic invocation it is sufficiently complete.

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 both parameters already have clear descriptions ('The .i domain name to delist' and 'The 0x seller address who created the listing'). The tool description adds no extra parameter detail, so the baseline score of 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?

The description uses a specific verb and resource: 'prepare an unsigned transaction payload' to 'cancel an active marketplace listing.' This clearly distinguishes it from sibling tools like marketplace_cancel_offer and marketplace_list_domain, which target different actions.

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?

The context establishes that this tool is for canceling an active marketplace listing, and the 'requires seller wallet signature' note implies when it is appropriate. However, it does not explicitly contrast it with alternatives such as marketplace_cancel_offer or state when not to use it.

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