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

Adds real behavioral context beyond the annotations: only eligible orders, cancellation notices are dispatched (a downstream side effect), and signed-in browser approval is required. This complements destructiveHint/idempotentHint 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?

A single front-loaded sentence with no filler, leading with the core action. It is efficient, though it could afford one more clause to clarify eligibility and confirmation_id.

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?

The output schema removes the need to describe return values, and annotations cover the safety profile. Still, the description leaves 'eligible' undefined and says nothing about the three input parameters, which is a gap for a destructive, non-idempotent operation.

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 0% across three parameters, so the description carries the full burden, yet it explains none of them. 'signed-in browser approval' vaguely gestures at confirmation_id but never connects it, and reason/order_id are entirely undefined.

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 (customer order), plus the side effect of sending cancellation notices. It is distinguishable from siblings like cancel_payment_attempt, though it doesn't explicitly name an alternative.

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?

Implies usage conditions via 'eligible' and 'signed-in browser approval', giving some context for when this applies. However, it never defines eligibility, states prerequisites precisely, or points to alternative tools for ineligible cases.

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