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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is known. The description adds extra behavioral context beyond annotations by explaining that earnings settle 'non-custodially to your withdrawal address on release,' which tells the agent that the tool returns account state rather than moving funds. It also clarifies the composition of 'earned' via 'released escrows plus claimed rewards.' No contradiction with 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?

Two sentences with no wasted words. The purpose is front-loaded, and the second sentence packs a dense list of outputs into a single readable clause. Every phrase adds value, and the read-only/non-custodial caveat is placed efficiently at the end.

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 zero-argument read-only tool with an output schema present, the description fully covers what the agent needs: what the tool returns, the scope (seller earnings), and the behavioral caveat. Nothing is missing that would prevent correct invocation or interpretation.

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 input schema has zero parameters and explicitly states the owner is derived from the authenticated principal. With no parameters to document, the description carries no burden here; the baseline of 4 applies because the schema-description coverage is essentially complete and the description adds context about which data is returned.

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?

Opens with an exact verb and resource: 'Check how much I have earned and what is pending.' The description then enumerates the specific returned data (lifetime USDC as seller, in-flight pending, unclaimed rewards, payout balance, buyer spend, reputation), leaving no ambiguity about what the tool does and how it differs from any generic read tool.

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 clearly frames the tool as the earnings check for the authenticated principal, and the read-only note signals it is safe to invoke when the user asks about earnings. There are no sibling tools for earnings, so explicit exclusions are unnecessary; clear context without alternatives is sufficient.

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