now_view_cart

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

With no annotations, the description carries the full burden; it does disclose the 'Read-only' nature and the exact payload contents, which is real value. It omits what happens with an empty cart, whether authentication/session state is required, and any rate-limit or freshness considerations, so meaningful behavioral gaps remain.

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?

A single front-loaded sentence lists the resource first and then the returned fields, with a two-word safety tag at the end. Nothing is repeated or padded.

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?

There is no output schema and no annotations, so the description reasonably compensates by enumerating return fields. For a parameterless read tool it is nearly complete; only empty-cart behavior and any prerequisite state are unaddressed.

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 nothing for the description to disambiguate beyond confirming it acts on the current cart with no filtering arguments. Baseline 4 applies for a parameterless tool.

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 verb ('Show') and resource ('the current Amazon Now cart') and enumerates the returned data (items, quantities, line totals, total, savings, benefit progress). It is clearly distinguishable from siblings like now_add_items and now_set_cart_quantity, which mutate rather than display the cart.

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 by the verb 'Show' and the 'Read-only' tag, so an agent can infer this is the inspection tool. However, it never names an alternative or an exclusion — it does not say to use now_set_cart_quantity when the cart needs changing, nor when to call now_search beforehand.

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