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

The readOnlyHint annotation already establishes that this is a safe read, so the bar is lower, but the description adds almost nothing beyond that: no pagination behavior, no whether inactive/expired coupons are included, and no return shape. The endpoint path is the only additional detail and it is redundant with the tool's nature.

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, front-loaded fragments with no waste. It is terse to the point of being telegraphic, but nothing needs to be cut.

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 zero-parameter list tool with no output schema, the description covers the minimum: what entity is returned. It omits what a pricing coupon actually represents in this domain and whether the list is scoped to the company or broader, which would help an agent decide relevance.

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?

The tool takes zero parameters, so the baseline is 4. There is nothing for the description to disambiguate, and the absence of filters is implicitly consistent with the empty schema.

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 names the specific resource (pricing coupons of the company), and the endpoint path 'GET /pricing_coupons.api' confirms it is a read. It does not distinguish this from sibling list tools such as list_payment_options, so the agent must infer from the name that this returns discount/pricing coupons rather than payment methods.

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?

There is no guidance on when to call this tool, what it is useful for, or whether any alternative exists. The agent gets a resource label and nothing about the conditions that select this tool over the other list_* siblings.

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