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

readOnlyHint=true already tells the agent this is a safe read, so the description's only added content is the REST endpoint mapping, which does not affect invocation. It says nothing about pagination defaults, total counts, response shape, or whether coupons and vouchers overlap – behavior an agent actually needs for a paged list call.

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 sentences, resource first, with zero filler. The endpoint sentence is marginally useful for API cross-referencing but is close to padding given the tool already names the resource.

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-required-parameter read-only list with fully documented parameters and no output schema, this is minimally viable. It falls short on the one thing the description alone could supply: how coupons relate to the similarly named voucher listing.

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%, and each of limit, offset, accept, and fields is documented in the schema itself. The description adds no extra meaning (e.g., default page size or typical use of 'accept'), so the baseline 3 applies.

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 ('List discount coupons') plus the underlying API endpoint, so the agent knows exactly what it retrieves. It does not distinguish the tool from the sibling bookingkit_list_vouchers, which is a real ambiguity for an agent choosing between coupon and voucher listings.

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 statement of when to use this tool versus bookingkit_list_vouchers or any other listing sibling, and no exclusions or prerequisites. The agent must infer usage purely from the name.

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