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

Beyond the annotations (destructiveHint=true, idempotentHint=false, openWorldHint=true), the description adds genuinely non-obvious behavior: cancellation is hosted and terminal, requires no on-chain broadcast or gas, and a committed taker reservation suspends termination until the fill settles or releases. It does not cover auth/proof prerequisites or idempotent-retry semantics, but the preconditions and the suspension state are real value the annotations cannot convey.

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 sentences, front-loaded with the action and identifier choice, then the terminal/hosted semantics, then the one edge case (taker reservation suspension). No sentence repeats the title or the schema, and nothing is padding.

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?

With an output schema present, return values need not be described, and the 100%-covered 7-parameter schema carries the auth and idempotency detail. The description covers the mutation's consequence and the suspended-order state, which is the main thing an agent could get wrong; only explicit sibling routing and error/retry behavior are absent.

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%, so every parameter including clOrdId, orderHash, and the wallet-proof fields is already documented in the schema. The description only restates that the target may be given as a hash or client order id and adds no format, precedence, or conflict guidance beyond that baseline.

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 first sentence gives a specific verb and resource ('Cancel an order') and names the two identifier modes (order hash or client order id), so the agent knows exactly what the tool acts on. It does not, however, distinguish itself from the confusable siblings problee_cancel_orders, problee_cancel_all_orders, or problee_confirm_order_cancel, so the agent must infer whether this is the singular, authoritative path.

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?

Usage is only implied: 'authoritatively' plus 'Provide this OR orderHash' signals a targeted single-order cancel as opposed to a bulk one, and 'terminal' implies no follow-up confirmation step is needed (relevant against problee_confirm_order_cancel). No sentence explicitly states when to choose this over those siblings or 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.