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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is fully covered structurally. The description adds nothing beyond that — no note on what happens with an invalid or missing coupon ID, no auth/scope requirements, and no return-shape context.

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 front-loaded sentence with zero waste and the resource identified immediately. It is efficient, though arguably so terse that it leaves useful routing and behavioral information unstated.

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 simple single-record read with full schema coverage, no output schema, and annotations carrying the safety profile, the description is adequate — the agent has everything needed to invoke it. Only the absence of sibling routing keeps it from being fully complete.

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 description coverage is 100%: 'id' is documented as 'Coupon ID' with an exclusiveMinimum constraint, and 'site_id' explains the multi-site targeting case. The description adds no format or syntax detail beyond the schema, 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 (Get) and resource (WooCommerce coupon) with the qualifier 'specific' implying a single record. It is clear against woo_list_coupons by implication, but never names the sibling or explicitly contrasts single vs. list retrieval.

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 when-to-use guidance, no prerequisites, and no mention of the alternative (woo_list_coupons) or when this is preferred over it. The agent must infer the single-record use case entirely from the name and 'specific'.

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