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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower, and the description earns credit for the auth requirement and for explaining the earnings lifecycle (pending until the partner pays, then payable after the hold). It stops short of return shape or pagination/rate-limit detail, so it isn't 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?

Two sentences with no filler, and the auth prerequisite is front-loaded. It is dense but every clause adds information; only the earnings-status parenthetical could be tightened.

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?

For a single-parameter read tool with no output schema, the description does convey what comes back and the meaning of the earnings statuses. It is incomplete on the one thing the agent must supply, the `days` window, leaving a meaningful gap.

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?

There is one parameter, `days`, and schema description coverage is 0% — neither the schema nor the description explains it. The description never mentions the time window at all, so it fails to compensate for the coverage gap (default 30, max 365 is left for the agent to infer).

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?

The description names a specific resource and enumerates what it returns: visits, partner clicks, and earnings broken out by status. An agent knows this is a read-only reporting tool. It does not distinguish itself from sibling payout/confirm tools (partner_confirm_payout, partner_payout_method), so it falls short of a 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 only directive is an auth prerequisite ('Needs your API key or OAuth token'), which is a condition rather than when-to-use guidance. Nothing tells the agent when to reach for partner_stats versus partner_confirm_payout or partner_payout_method, and no exclusions or alternative routes are named.

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