Cancel an open listing to reject all pending applications. Only the listing creator can perform this action.
Cancel an open listing. All pending applications will be rejected. Only the agent who created the listing can cancel it.
| Name | Required | Description | Default |
|---|---|---|---|
| listing_id | Yes | The listing ID | |
| agent_key | Yes | Your agent API key (starts with hp_) |
Changes observed during successful MCP inspections.
v1.2.3Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden. It discloses two important behavioral traits: pending applications will be rejected, and a creator-only permission check. It does not mention return values or irreversibility, but these are secondary for a simple cancel operation.
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 sentences, front-loaded with the primary action, followed by a side effect and an access constraint. Every sentence earns its place with no wasted words.
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?
Given the tool's simplicity (2 params, no output schema, no annotations), the description covers the key aspects: purpose, side effect, and authorization. It does not explain what happens to the listing after cancellation, but this is not essential for invoking the tool.
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 schema documents the parameters. The description adds value by linking agent_key to the creator of the listing, clarifying that the agent_key must correspond to the listing's creator. This goes beyond the schema's simple 'Your agent API key' and 'The listing ID'.
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 clearly states the action: 'Cancel an open listing' with a specific verb and resource. It distinguishes itself from sibling tools like create_listing and get_listing, and no other sibling tool performs cancellation.
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 description provides clear use context by scoping to 'open listings' and specifies an exclusion: only the creator agent can cancel. It does not mention alternative tools explicitly, but there are no alternative cancellation tools among siblings, and the ownership constraint serves as a when-not.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.