getReferralCommissionRecords

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

Annotations only declare readOnlyHint and openWorldHint; the description goes well beyond them. It discloses server-side validation behavior ('MCP rejects malformed or invalid calendar dates', rejects pageSize above 200 'to prevent silently falling back to 10'), normalization rules (page 0 becomes 1, pageSize 0 becomes 10), and output traits (invitee userIds masked, paymentTime is Unix seconds). That is exactly the kind of non-obvious behavior an agent cannot get from the 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?

Purpose is front-loaded in the first sentence, then filters, then validation/normalization rules, then return-value notes — a sensible order. Every sentence carries information, though the middle section is dense and packs several distinct rules into long clauses that could be split for scanability.

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 six optional parameters, no output schema, and zero schema coverage, the description does the heavy lifting on input formats and adds return-value hints (masked userIds, Unix-second paymentTime). The main omission is the meaning of the productLine enum values and any indication of what other fields a commission record contains. The warning against inferring a default time window is a useful completeness signal.

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 description coverage is 0%, so the description carries the full burden and mostly does: it pins the datetime format, clarifies page is a uint32 with 0-normalization, gives the 0–200 pageSize band with its normalization, and identifies userIdList as invitee IDs. The gap is productLine, whose enum values (0,1,2,3,4,6,9) are never explained, leaving the agent unable to pick a value.

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 plus the owning subject: 'Query referral commission records for the authenticated inviter.' That clearly separates it from other referral siblings like getReferralCampaignRewards or getReferralUserInvitations by resource type. It stops short of explicitly naming a sibling to disambiguate against, so it lands at 4 rather than 5.

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 implies usage through its filter list ('Optionally filter by invitee IDs, time range, product line, and page') and adds a caution not to infer a default time window. However, it never states when an agent should choose this over getReferralCampaignRewards, queryReferrals, or getReferralUserInvitations, nor does it set any preconditions. Usage is inferable but not spelled out.

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