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

Annotations already declare destructiveHint=true, idempotentHint=false, and readOnlyHint=false, so the safety profile is known. The description adds real behavioral context on top: the AI stops monitoring the order, the status transitions to 'cancelled', and it cannot be reactivated. It does not explain failure modes (e.g., cancelling an already-terminal order), so it falls short of a 5.

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?

Four tight sentences, front-loaded with the action, then consequences, then the alternative. Every sentence carries information an agent needs; 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?

For a single-parameter mutation with no output schema, the description supplies the missing outcome information (status becomes 'cancelled', monitoring stops, no reversal) and the routing alternative. Nothing an agent needs to call this correctly is 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?

With one parameter at 100% schema description coverage, the schema already documents orderId fully. The description adds no formatting, range, or sourcing detail beyond what the schema provides, 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?

States a specific verb and resource ('Cancel an active conditional order') with a clear qualifier that this applies only to active orders. It also names the sibling alternative (update_conditional_order) for the pause case, so an agent can separate it from adjacent conditional-order tools without inspecting schemas.

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?

Explicitly handles the when/when-not decision: cancel when the order should never run again, versus update_conditional_order with enabled=false to temporarily pause monitoring. This is exactly the ambiguity an agent would face given siblings like update_conditional_order, delete_conditional_order, and cancel_suggested_order.

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