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

Annotations already declare readOnly/idempotent/non-destructive/non-open-world, so the safety profile is covered. The description adds real value beyond that by clarifying the boundary: payout requests and payment requisites are intentionally excluded and remain in the partner dashboard, which prevents the agent from trying to use this tool for a write flow.

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?

Two sentences, front-loaded with the returned payload and followed by the read-only scope caveat. No filler; every clause carries informational weight.

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 compensates by enumerating the returned fields (balance, withheld, referral list, accruals, source labels) and the scope limit. Adequate for an agent to call it correctly, though it does not mention pagination behavior for the referral list.

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%, so limit, date_from, date_to, and source_id are already fully documented. The description alludes to the period-based accruals and source labels that these params feed, but adds no syntax or format detail beyond the schema; baseline 3 applies.

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 ('Возвращает партнёрскую статистику текущего пользователя') and enumerates the returned content: balance payable, withheld, referral list with payment counts, period accruals, and source labels. This lets an agent distinguish it from the mutation sibling manage_partner_source without opening the schema.

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?

Frames the use case clearly ('сколько я привёл и сколько заработал') and scopes it to the current user, and explicitly states what it does not cover (payout request and payment details live in the partner dashboard). It stops short of naming an alternative read tool, but no genuine alternative exists among the siblings.

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