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

No annotations provided, so the description fully discloses behavior: it returns both active and exhausted redemptions with specific statuses. It also states it's 'Free' (cost implication). However, it doesn't describe potential side effects, but since it's a list operation, this is sufficient.

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 description is two sentences, front-loaded with the verb and resource. Every sentence adds value: the first states the primary purpose, the second adds details about return content and a prerequisite. No unnecessary words.

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?

The description covers the main behavior and return values, and output schema exists so return details are adequate. However, it omits explanation of the 'dpop_token' parameter and the broader context of the 'free' claim (e.g., what conditions apply). Given the tool has 2 parameters and no annotations, the description should be more 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 0%, and the description does not explain the 'dpop_token' parameter. It only hints that 'npub' is required ('requires proof of npub'), but does not elaborate on its format or the role of 'dpop_token'. With no parameter details in the description, it fails to compensate for the schema's lack of descriptions.

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 clearly states the tool lists redeemed coupons for a patron on an operator, using the verb 'list' and specifying the resource as 'coupons this patron has redeemed'. It distinguishes from sibling tools like 'weather_list_coupons' by focusing on patron-specific redemptions.

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 description mentions a prerequisite ('requires proof of npub') and implies it's for listing redeemed coupons, but does not explicitly state when to avoid this tool or mention alternatives like 'weather_list_coupons' for all coupons. Clear context but no exclusions.

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