Cancel Pending Order

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

The description adds meaningful behavioral context beyond the annotations: cancellation is not guaranteed if being filled, a successful response means the request was accepted, and the rate limit is specified. This complements the destructiveHint and idempotentHint annotations without contradicting them.

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?

Three short sentences deliver the essential information with no redundancy. The description is front-loaded with the core purpose, followed by caveats and rate limit.

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 simple one-parameter cancel operation with no output schema, the description covers the key points: what it cancels, a critical failure caveat, and the meaning of a successful response. It could also address behavior for invalid or already-canceled orders, but that is not essential.

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% for the single parameter orderId, which already explains it as 'The unique numerical ID of the order to cancel.' The tool description merely says 'by its unique ID' without adding further detail, so the baseline 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 clearly states the verb and resource: 'Cancel an active, unfilled order by its unique ID.' It distinguishes this tool from siblings, all of which are either get or place operations, with no other cancel tool present.

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 when to use it (to cancel an active, unfilled order) and includes an important caveat about orders being filled, but it does not explicitly name alternatives or state 'use this instead of X.' Since there are no competing cancel tools, the guidance is adequate.

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