cancel_order

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

With no annotations, the description bears the full burden. It adds the behavioral nuance of 'immediately' and limits the action to pending or active orders, but it does not disclose potential failure conditions, irreversibility, or side effects. This is adequate but not rich, and there is no contradiction with annotations since none exist.

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 a single, concise sentence that immediately conveys the tool's purpose. It contains no filler or redundant information and is well-structured for quick understanding.

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 simplicity of the tool (one parameter), the description covers the core action and constraints, while the schema handles the critical ID nuance. The existence of an output schema covers return values. The description could mention what happens if the order is already filled or no longer cancellable, but overall it is sufficiently complete for its scope.

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?

The input schema has 100% description coverage with a detailed explanation of the client_order_id distinction, so the main description does not need to add parameter details. It adds no meaning beyond the schema, and per the baseline for high coverage, a score of 3 is appropriate.

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 identifies the tool as canceling a pending or active order on the Webull account, using a specific verb and resource. It distinguishes itself from sibling tools like draft_order and preview_order by focusing on the cancellation action and specifying the order states it applies to.

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 implies usage when an order is pending or active, but does not explicitly state when to use it versus alternatives. There is no alternative cancel tool listed, and the schema description for order_id indirectly references get_open_orders for finding the client_order_id, providing some guidance without being explicit.

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