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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds only that status is returned alongside keys and cites the REST endpoint; it does not disclose pagination defaults, whether revoked/expired keys are included by default, or any rate/auth constraints. With annotations doing the heavy lifting, this is adequate but thin.

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 short sentences, with the resource and return content front-loaded before the endpoint reference. Nothing is bloated, though the bare endpoint citation adds little for most agents.

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?

A read-only list tool with fully documented parameters and clear annotations needs little prose, so this is close to sufficient. It still omits pagination behavior and result-set scope, which an agent calling a paginated list endpoint would benefit from knowing.

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%, and each of the five parameters is documented in the schema with its meaning and constraints. The description adds no additional parameter meaning (e.g. filter combination behavior), so 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 and resource ('List issued licence keys') plus the underlying endpoint, so the agent knows exactly what the tool does. It does not differentiate itself from the many other polar_list_* siblings (orders, products, subscriptions), but the resource is unambiguous.

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?

No guidance on when to use this versus alternatives, no mention of prerequisites or that filters like status/benefit_id exist to narrow results. The agent must infer usage entirely from the name and schema.

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