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

Annotations already declare readOnlyHint=true, openWorldHint=true, destructiveHint=false, and the description usefully adds the authentication requirement (affiliate's own token) and an explicit data-boundary exclusion. It does not cover failure modes or rate limits, so not a 5.

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?

A single dense sentence, front-loaded with the resource identity followed by the scope constraint. No filler, no restatement of the title.

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 an output schema present, return values need not be described, and the annotations plus the description's auth/scope statement cover what an agent needs to call it. Minor gap: no guidance on locale/error behavior if the token is absent.

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?

Only one parameter (locale) and schema description coverage is 100%, including a well-written enum explanation, so the schema carries the full burden. The description adds no parameter-level detail, which is the expected baseline here.

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 resource (the affiliate's own profile) and enumerates the concrete payload fields — referral code, account state, public affiliate page — so an agent can tell it apart from my_referrals, my_earnings, and my_service_links at a glance.

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?

Gives clear usage context: it requires the affiliate's own token, answers for nobody else, and holds nothing about a customer — effectively a when-not boundary against customer-facing or admin lookups. It stops short of naming which sibling to call instead for related data.

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