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

No annotations are provided, so the description carries the behavioral disclosure burden. It only says 'Create', which implies mutation, but it does not disclose side effects, uniqueness conflicts, ownership verification, or any constraints beyond the schema. This is a significant gap for a state-changing tool.

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?

The description is a single, tightly worded sentence with no filler. It front-loads the action and object clearly, making it easy for an agent to parse quickly.

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 schema is rich with parameter details and an output schema exists, so the description does not need to explain return values. However, the description omits operational context such as authentication prerequisites, how operator ownership is enforced, and the distinction between this tool and update_coupon. The undocumented dpop_token parameter further contributes to the gap.

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 high at 86%, and parameter descriptions are detailed. The tool description adds no parameter-specific meaning, but the schema already documents name, discount_percent, valid_from, valid_until, total_uses, and uses_per_patron well.

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 ('Create'), the resource ('discount coupon'), and the ownership scope ('operator-owned'). This differentiates it from update, delete, list, and redeem coupon siblings without needing to inspect 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?

The description establishes a clear usage context: creating a new operator-owned coupon. It does not explicitly name alternatives like update_coupon or delete_coupon, but the 'create a new' phrasing provides enough context for an agent to select this tool over its siblings.

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