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

Annotations already carry readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds valuable context beyond those hints: non-custodial settlement, withdrawal address on release, and the distinction between released escrows, claimed rewards, pending amounts, and claim-later rewards. This meaningfully enriches what the agent knows about behavior without contradicting 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?

Two sentences, front-loaded with the core purpose. The second sentence is a dense enumerative list of return components, which is informative but slightly run-on. Every element contributes value, so the description earns a high score, though it could be broken up for easier scanning.

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 provided, the description takes on the responsibility of explaining return values, and it does so thoroughly: lifetime earned, pending amounts, unclaimed rewards, payout-address balance, buyer spend summary, and reputation. It also clarifies the settlement model. The only minor gap is that it doesn't specify response structure or units, but the tool has no arguments and the semantic content is sufficient for selection and invocation.

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, and the schema already explains that the owner is derived from the authenticated principal. With 0 params, the baseline is 4, and there is nothing missing for an agent to invoke it correctly.

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 verb ('Check'), a clear resource ('earnings'), and a scoped subject ('as seller'). It goes on to enumerate precisely what is returned, which fully distinguishes it from the sibling tools about contracts, actions, and onboarding. The agent can tell exactly what this tool is for.

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?

Usage is implied rather than explicit: the phrase 'Check how much I have earned and what is pending' tells an agent when to invoke it, and the seller/buyer scoping adds context. However, there is no explicit statement of when to use this versus a sibling, no exclusions, and no mention of prerequisites. It meets the minimum viable bar but leaves routing guidance to inference.

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