getReferralUserIdentityProfile

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

Annotations already declare readOnlyHint and openWorldHint, so the description's job is to add context, and it does: it warns that missing relationship records are normal, that related fields may sit at defaults, and that commissionInfo appears only when a matching M1 inviter record and commission data exist. That is genuine disclosure about partial results an agent would otherwise misread as errors, though it does not discuss data freshness or any auth scope caveats beyond the API key owner.

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?

Four sentences, front-loaded with the purpose, then the no-input constraint, then the two field caveats. Every sentence carries information; the only minor weakness is that the last sentence ('Missing relationship records are normal...') partially restates the commissionInfo conditional without adding new precision.

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?

There is no output schema, so the description justifiably spends its words explaining return-field semantics and partial-result conditions, which is exactly what an agent needs for a readWith-zero-params tool. It stops short of enumerating what the profile actually contains (identity fields, affiliate tier, etc.), but the coverage is adequate for a simple self-scoped read.

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 schema has zero parameters, which is the baseline-4 case, and the description correctly reinforces this by stating there is no user ID input. It also clarifies that inviterAffiliateUserId and inviterUserId are 0/1 relationship indicators rather than actual IDs, which prevents a common misinterpretation of returned fields.

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: querying the authenticated API key owner's referral identity, affiliate status, and inviter/invitee relationships. This scopes it to the caller's own profile, which separates it from list-style siblings like getAffiliateUserList or getReferralCommissionRecords, though it never names those siblings explicitly to confirm the boundary against getAffiliateUserInfo.

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 sentence 'The request has no user ID input' establishes clear usage context: this is a self-scoped lookup, not a parameterized lookup for arbitrary users. It implies when the tool applies but provides no explicit exclusion or routing to the neighboring affiliate/referral tools that return third-party data.

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