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

readOnlyHint=true already declares the safety profile, so the bar is lower, but the description adds only the raw endpoint path — no information on result ordering, pagination behaviour, or what a voucher record contains. It neither contradicts nor meaningfully enriches the annotations.

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?

A single compact sentence that front-loads the action and scope. The trailing endpoint path is low-value filler but the description stays short and readable.

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?

A simple read-only list tool with fully documented params and safety annotations, so most needs are met. However, with no output schema, the agent still has no idea what fields a voucher returns or how results are paged — a brief note would close the gap.

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 parameter (page, per_page, currency_id) is documented in the schema. The description adds only a restatement of the currency filter, so 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?

Specific verb+resource ('List discount vouchers') with an optional currency scope, and the endpoint path confirms the resource. It is clearly distinct from the many other list_* siblings such as list_bookings or list_all_currencies, though it doesn't say so explicitly.

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?

'optionally for one currency' hints at a filter but gives no guidance on when to use this versus other pricing/offer list tools (e.g. list_booking_offers), no mention of pagination defaults, and no exclusions.

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