cancel_order

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

The annotations already disclose that the tool is non-read-only, destructive, and interacts with the open world. The description adds the prerequisite that trading must be enabled, which is useful context, but it does not disclose potential failure modes (e.g., order already filled), the irreversibility of cancellation, or any rate limits. While it avoids contradicting the annotations, the added behavioral context is minimal.

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 sentence with two clear statements: what the tool does and a required environment variable. It is concise, front-loaded, and contains no redundant information.

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 that this is a destructive action with real-world implications (openWorldHint=true), the description is too sparse. It omits details about error handling, order state checks, and the effect of cancellation. While an output schema exists, the description should still provide sufficient context for safe usage, which it does not.

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 provides two parameters (order_id and account_seq) with no descriptions, and the tool description does not explain their meaning or usage. At 0% schema description coverage, the description should compensate, but it fails to clarify what order_id refers to or when account_seq is required, leaving the agent uncertain about invocation.

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 the specific verb 'Cancel' and identifies the resource as 'an open order,' clearly distinguishing this from sibling tools like create_order, modify_order, and get_order. It succinctly states the tool's function without ambiguity.

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 states a prerequisite (TOSS_ENABLE_TRADING=true) but does not provide any guidance on when to use this tool over alternatives, nor any exclusions or preconditions beyond the flag. The use case is implied by the name and purpose, but no explicit direction is given.

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