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

Annotations already declare destructiveHint, idempotentHint, and readOnlyHint=false, so the safety profile is covered. The description adds genuinely new operational context: that bulk cancellation should be confirmed with the user and that event filtering has a dependency. It does not describe failure modes or partial-cancel behavior.

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?

Two short sentences that front-load the primary action, then layer the scoping rules and the safety instruction. No filler or restated framing.

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 two-parameter bulk mutation with full annotation coverage and an output schema, the description covers scope, filtering dependencies, and the confirmation requirement. Nothing an agent needs before invoking is missing.

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 both parameters are already documented, including the 'requires sport' constraint on event_id. The description repeats rather than extends that information, so the baseline of 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 ('Cancel') and resource ('every open order') with explicit scope, and the 'every' distinguishes it from the sibling close_order which handles a single order. An agent can route correctly without opening either schema.

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?

Gives clear operating conditions: narrowing by sport, and that narrowing by event requires the sport. It also flags the confirmation prerequisite. It does not explicitly name close_order as the single-order alternative, so sibling differentiation relies on the 'every' wording rather than an explicit pointer.

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