create_coupon

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

With annotations limited to openWorldHint: false, the description carries the main behavioral disclosure. It adds useful constraints (unique code, supported discount types) but does not cover potential side effects, auth requirements, or error behavior. The create verb implies mutation, but no further safety or irreversible-action context is given.

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 short, purposeful sentences. The first states the action, the second adds a key constraint, and the third gives a performance tip. No filler or redundancy.

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 13-parameter create tool with no output schema, the description is somewhat minimal. It does not explicitly describe the return value (though fields param implies object retrieval) or permissions/error cases. However, the schema covers all parameter semantics, and the openWorldHint provides some closure. It's adequate but leaves gaps.

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 coverage is 100%, so parameters are already documented. The description adds meaning to 'code' by stating it must be unique, and to 'fields' by advising to request only needed fields. It also reinforces the discount_type enum values. This goes slightly beyond the schema's 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 description opens with 'Create a discount coupon,' a specific verb and resource. It further distinguishes the tool by listing supported discount types (percent, fixed cart, fixed product) and a unique-code constraint, clearly separating it from sibling tools like update_coupon or list_coupons.

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 clearly indicates this is the tool for creating coupons ('Create a discount coupon') and adds practical usage advice ('Use fields param to request only needed fields'). However, it does not explicitly mention alternatives or when not to use it, such as pointing to update_coupon for existing coupons.

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