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

Annotations already indicate readOnlyHint=false and destructiveHint=false, so the description adds value by disclosing the side effect on seller ratingAvg and the conditional delivery confirmation. This goes beyond what the schema or annotations provide.

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?

The description is three short sentences that each convey a distinct piece of information: the action, the conditional behavior, and the side effect. There is no wasted wording.

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 tool with three parameters and no output schema, the description covers the core behavior, the conditional action, and the outcome. The missing 'note' parameter is a minor gap, but overall the description is sufficiently complete for the tool's simplicity.

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?

With 0% schema description coverage, the description must compensate. It mentions the rating scale (1-5) and implies purchaseId as the target, but it does not explain the 'note' parameter at all. The rating scale is already in the schema as min/max, so the description adds minimal new information.

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 clearly states the tool's function: the buyer rates a purchase on a 1-5 scale and updates the seller's rating average. It uses a specific verb ('rates') and resource ('purchase'), and the conditional delivery confirmation distinguishes it from sibling tools like confirm_delivery.

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 indicates when the tool is applicable by specifying the buyer role and the conditional behavior when escrow is still held. It does not explicitly name alternatives or say when not to use it, but the context is clear enough for an agent to decide.

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