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

While annotations supply readOnly=false, idempotent=true, openWorld=true, destructive=false, the description adds the crucial boundary: 'This action cannot place an order or collect payment.' This prevents an agent from assuming the checkout handoff completes a sale, which is exactly the kind of behavioral disclosure annotations don't capture.

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: the action, the precondition, and the non-effect are crisp and front-loaded. Every clause earns its place.

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 5-parameter mutation tool with an output schema, the description covers purpose, preconditions, and side-effect boundaries. It doesn't mention how requestId relates to the previous offer/qualification flow, so an agent must infer that from the schema and sibling names, but nothing essential to a correct invocation is missing.

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?

Schema description coverage is 0%, so the description must compensate. It adds business meaning for buyerConfirmedCheckoutHandoff and buyerAcknowledgements by tying them to the explicit-request and acknowledgment conditions. However, requestId is never explained, and sku/quantity are left entirely to their const values, leaving a partial compensation gap.

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?

States a specific action ('Create a Shopify-hosted checkout handoff') and the exact resource (the approved fire-pit configuration), and distinguishes itself from sibling configuration/catalog/offer tools by focusing on the post-approval checkout step. The description also names the condition that triggers it, making its role unambiguous.

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?

Explicitly states when to use the tool: 'only after the buyer explicitly requests this exact approved fire-pit configuration and acknowledges...' This is strong when-to-use guidance. It doesn't name alternative tools for not-this-case scenarios, but the sibling names make the alternatives clear enough.

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