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

The annotations already declare the tool as read-only, idempotent, non-destructive, and closed-world. The description adds useful behavioral context beyond that: the link parameter format, 30-day attribution window, 10% margin reward, and where agents should pass the code.

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 tight sentences with no wasted text. It front-loads the returned resource and then adds the attribution and usage details.

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 zero-parameter read tool with no output schema, the description is complete enough: it explains what is returned, the link format, attribution duration, reward, and how the code is used. The annotations cover safety behavior.

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 no input parameters, so there are no parameter semantics to explain. Per the baseline for zero-parameter tools, a 4 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 clearly states that the tool returns the caller's referral code and shareable link, with the link format shown. It distinguishes the returned resource from sibling get_referral_stats by focusing on the code/link rather than statistics, though it does not explicitly name that sibling.

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 explains how to use the resulting ref code on create_order, create_cart, or transfer_domain, which implies the tool's role in obtaining that code. However, it does not explicitly say when to call get_referral_link versus get_referral_stats or other referral-related tools.

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