create_coupon

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

Goes meaningfully beyond the destructiveHint=true annotation by disclosing that the first call is a non-mutating preview and that mutation only occurs with confirm:true plus the returned token. It does not say what the preview contains, whether the confirm call is idempotent, or what happens if the token expires.

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 tight sentences with the primary purpose and the safety-critical write protocol front-loaded, and the confirming mechanism second. No filler.

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 destructive 5-parameter tool with no output schema, the description covers the confirm protocol but leaves the required identifiers and the preview's return contents unexplained, so an agent could still mis-invoke on the first call.

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 only 40%, and the description compensates only for confirm/confirmToken, which the schema already documents. The three required params (programId, partnerId, code) get no semantic explanation from either source — no format, uniqueness constraint, or referential requirement is stated.

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 ("Create a coupon code") plus the scope detail that it attributes to a partner. No sibling creates coupons, so there is nothing to confuse it with, but it never contrasts with create_link or other creation tools, leaving differentiation implicit.

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 gives a clear invocation protocol for the two-call preview/confirm flow, which is real usage guidance. It never states prerequisites (must the program and partner already exist? must the code be unique?) or when to prefer this over create_link.

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