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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true. The description adds meaningful context beyond that: coupon codes are masked with specific rules, coupon_code_masked is returned, nothing is redeemed or voided, and it is a V3 Loyalty 2.0 endpoint. It does not mention rate limits or pagination behavior, which keeps it from a 5.

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?

The purpose is front-loaded and the extra sentences are short and useful. The long parenthetical listing fields and masking rules is dense but each detail earns its place for a report tool without an output schema.

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?

With no output schema, the description compensates by listing the returned fields and explaining the masking behavior of coupon codes. Combined with the read-only audit framing and the schema's pagination documentation, an agent has what it needs to call the tool correctly.

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%, so both page and limit are already fully documented in the schema. The description adds no parameter-level detail, so the baseline of 3 is appropriate.

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: a loyalty rewards report listing rewards customers earned or redeemed, with enumerated return fields. It clearly distinguishes rewards from generic customer/order/product tools, but does not explicitly differentiate itself from the sibling stamped_list_loyalty_activities.

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 implied by 'Loyalty program report' and 'Read-only audit view,' but there is no explicit when-to-use guidance, no when-not-to-use exclusions, and no named alternative such as stamped_list_loyalty_activities for activity-level data.

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