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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered structurally. The description adds useful content disclosure ('What You Get') but no behavioral traits such as error cases, missing-ID behavior, or permission requirements beyond what annotations provide.

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?

It is front-loaded and clearly sectioned, which helps scanning, but it is over-sized for a single-parameter lookup and contains tautological filler such as 'Complete voucher details - All information about the voucher' that duplicates the heading.

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 read-only lookup with no output schema and one fully documented parameter, the description's 'What You Get' section usefully enumerates the expected return fields (discount rules, validity, usage counts). Nothing essential is missing, though pagination/error behavior is not addressed.

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?

There is a single required parameter at 100% schema description coverage, so the schema fully documents voucherID. The 'Quick Start' line ('Provide the voucher ID in the URL path') only restates that it is a path parameter and adds no format or constraint detail beyond the schema; 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?

The Overview states a specific verb and resource ('Get complete details for a specific voucher by its ID') and enumerates the content scope (discount rules, validity, usage). This clearly distinguishes it from the sibling list tool get_vouchers and the history tool get_vouchers_history.

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?

The 'When to Use' section lists four scenarios, but they are generic (lookup, validation, display, support) and read as filler rather than decision criteria. There is no guidance on when NOT to use it or when to prefer get_vouchers / get_vouchers_history instead.

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