checkout_summary

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

With no annotations, the description carries the full burden, yet it only discloses that login is required. It does not say whether this is a read-only snapshot, whether it mutates or locks checkout state, or what "verified" implies about validity of the summary.

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 short sentences with no filler, but their brevity comes from under-specification rather than economy. The auth constraint is front-loaded, which is the one structural positive.

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 return values need not be described, and there are no parameters to cover. Still, an agent cannot tell from "checkout summary" what state this represents or where it fits in the checkout sequence alongside its many siblings, leaving the core question unanswered.

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 there is no parameter meaning to add; the baseline of 4 applies. The description does not need to explain arguments at all.

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?

"Checkout summary" essentially restates the tool name, and "Verified" adds an unexplained qualifier. The description never states what the summary contains (items, totals, fulfilment state?) or how it differs from siblings such as checkout_context or checkout_payment_options.

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 only guidance is the precondition "Requires login," which says nothing about when this tool should be chosen over checkout_context, checkout_cumulus_bons, or the other checkout-step tools. No alternatives or exclusions are named.

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