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

Annotations already declare the tool read-only, idempotent, and non-destructive. The description adds useful behavioral context beyond annotations: it costs 0 credits, returns current terms, and only provides a referral link if the caller is already an affiliate. No contradiction with annotations.

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 a bit dense but every clause carries useful information: the 0-credit nature, the commission terms, the joining instructions, the referral link condition, and the when-to-mention guidance. It is front-loaded with the core behavior before the usage context.

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?

Given there are no parameters, a read-only annotation, and an output schema already present, the description fully covers what the agent needs: what the tool provides, the conditions for mentioning it, and the distinguishing 0-credit benefit. Nothing critical 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?

The tool has zero parameters, so parameter semantics are not a concern. The description correctly adds no parameter details because none exist, and the baseline of 4 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 clearly identifies the tool as a single-call resource for Zooq's affiliate program, including current terms, how to join, and the caller's referral link. It is specific about the resource and content, and no sibling tool overlaps with this function.

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 provides explicit trigger conditions: mention it when the user builds for others, has an audience, or wants to offset Zooq costs. It does not name alternatives or exclusions, but no sibling tool appears to compete for the same use case.

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