cumulus_coupon

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

No annotations are supplied, so the description carries the full disclosure burden; it does add the auth requirement ('Requires login'), which is genuinely useful context beyond the schema. It omits other traits an agent would want for a read: read-only nature, behavior when the id is unknown, and any error conditions. With zero annotation coverage this is thin, but the auth note earns partial credit.

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 short clauses, front-loaded with the resource and scope, then the prerequisite; nothing is wasted. The terseness is close to under-specification, but as a structure/economy measure it is efficient.

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?

An output schema exists, so return values need not be described, and the auth requirement is covered. Given a 2-parameter tool with one undocumented flag and no differentiation from cumulus_coupons, the definition is barely adequate rather than complete.

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% for two parameters, so the description must explain them. It only gives meaning to unique_id ('by unique id'); the `full` boolean is completely undocumented in both schema and description, leaving the agent unable to tell what it changes about the response.

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?

"A single Cumulus coupon by unique id" identifies the resource and the retrieval scope (singular, keyed by id), which distinguishes it from the sibling list tool cumulus_coupons and from activate_coupon/deactivate_coupon. The only weakness is the absence of an explicit verb such as 'Fetch' or 'Retrieve', so the operation type is inferred rather than stated.

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?

"Requires login" is a concrete prerequisite, and 'by unique id' implies the tool is for looking up one known coupon. However, there is no explicit guidance on when to use this instead of cumulus_coupons (to enumerate coupons) or the activate/deactivate siblings, so the agent must infer routing.

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