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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds genuinely new behavioral context: the result is scoped to this connection's customer, contains no buyer details (a privacy constraint), and caps order history at the last 5 paid orders.

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?

Front-loaded with the action and the identity scope, and every listed return field earns its place since there is no output schema. The single long sentence is dense and slightly run-on, but no sentence is wasted.

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 correctly compensates by enumerating the return payload, and it covers the one optional parameter's conditional use. It stops short of saying what happens when the customer is not a referrer or has no payout destination configured, which an agent would need before calling.

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 coverage is 100% and the customerKey property already documents 'Omit when connected through a personal token URL,' so the description is largely restating the schema. It adds no format examples or error behavior for a wrong/missing key beyond the omit condition.

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+resource ('Show your referral summary as a GYOTAK referrer') and then enumerates exactly what the summary contains: referral URL, paid/unpaid order counts, estimated commission, unpaid balance, payout destination status, and last 5 paid orders. This clearly separates it from siblings like apply_referrer, report_share, get_share_kit, and register_payout.

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?

It gives a useful scoping rule ('only works for the customer of this connection') and a concrete connection-mode condition for omitting customerKey. However, it never names an alternative tool or states what to do if the caller is not yet a referrer (apply_referrer) or needs payout setup (register_payout), so routing is left implicit.

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