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

Goes well beyond the readOnlyHint/openWorldHint/destructiveHint annotations: explains that changes apply to the next buyer, that disabling preserves the coupon, the product_ids bump caveat, the default per-call confirmation, the 'reaches other people' warning, and the required API key scope. Rich operational context an agent needs before mutating.

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?

Front-loads the core purpose and packs multiple useful constraints into a compact block. Dense but nearly every sentence carries a distinct operational fact, with only mild redundancy between the confirmation sentences.

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 2-param mutation tool with no output schema, the description covers mutation semantics, side effects, prerequisites (API key), and confirmation behavior. Nothing critical is missing, though return/response format remains unaddressed.

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 baseline would be 3, but the description adds real meaning: it expands on the product_ids field by explaining new bumps are never auto-added and must be re-sent, which the schema does not convey.

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 (update) and resource (coupon), then enumerates exactly what can change: status, discount, dates, use limit, products. An agent can distinguish it from thrivecart_create_coupon and thrivecart_list_coupons without opening any 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?

Clarifies scope ('Changes one coupon') and the behavior distinction between disabling vs enabling, and the conditional case for re-sending product_ids after bumps are added. It does not explicitly name a sibling tool to use instead, but the conditions for use are clear.

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