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

Annotations already establish read-only, idempotent, non-destructive, closed-world behavior, so the bar is lower. The description still adds genuinely useful context not in the annotations: it is free, published Mondays, and the window and ledger coverage are carried in the body. It stops short of describing staleness guarantees or failure modes if no report has been published yet.

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?

Front-loaded with the one-word qualifier 'Free', then payload summary, then when/not-for, then publication cadence. Every clause carries distinct information and none repeats the annotations or schema.

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?

An output schema exists, so the description need not explain the return shape and correctly points to the body for window and ledger coverage. For a zero-parameter read tool, the alternatives, cadence, and cost are sufficient for an agent to decide and call correctly.

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 tool takes zero parameters, so the baseline of 4 applies and there is no schema semantics for the description to duplicate or compensate for. It correctly adds nothing parameter-related, though it makes no statement about determinism of the returned week (e.g. whether one report per week is retained).

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?

Names a specific resource (the latest published Agent Income Report) returned as JSON, and enumerates its contents: paying venues, worker wallets, flagged honeypots, x402 index health. That enumeration distinguishes it from siblings like settled_report, settled_status, and settled_events without needing their schemas.

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?

Explicit 'Use when' clause scopes it to the week's summary for a digest or a decision about where to look for work, and the 'Not for' clause names the exact alternatives (settled_status, settled_income_venues) that serve live numbers. When-to-use, when-not-to-use, and alternatives are all present.

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