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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=true, so the safety profile is covered. The description adds real value by disclosing the returned content (discounts, codes, availability, redeemed counts) despite there being no output schema, though it omits any auth or error semantics.

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 compact sentences, zero filler, with the resource scope front-loaded and the endpoint tacked on at the end. Every clause carries information.

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 single-param read tool with no output schema, the description supplies enough: what entity is fetched and which fields it carries. Annotations cover safety, and the schema covers the parameter, so nothing essential is missing.

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 the single coupon_id parameter is fully documented in the schema, including its provenance from ticketspice_list_coupons. The description adds nothing beyond 'by id', 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?

The description states a specific verb and resource ('One coupon by id') and enumerates the payload it returns (discounts, codes, availability, redeemed counts), which separates it from ticketspice_list_coupons. It never names the sibling explicitly, so differentiation is implied by 'one/by id' 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?

Usage is only implied: fetching a single coupon by id, with the schema noting the id comes from ticketspice_list_coupons. There is no explicit when-to-use-vs-list guidance or note about behavior when the id does not exist.

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