cart_get

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

readOnlyHint=true and openWorldHint=true already cover the safety profile, and "inspect" is consistent with that. The description adds little beyond it: no note about per-account scoping, whether an empty/uninitialized cart errors or returns empty, or refresh/freshness behavior of the "official" cart.

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 tight sentence with the resource and returned content front-loaded and no filler.

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?

No output schema and no annotation detail on return shape, combined with a surprising required-parameter set that the description never addresses. For a tool whose inputs look mismatched to its read-only purpose, the description should at minimum explain the scoping/identity parameters.

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% and the single required parameter is an opaque nested 'request' object whose required fields (account, store_code, pickup_at, max_amount_cny) look like checkout inputs rather than cart-read inputs. The description explains none of this, so an agent has no idea why a read requires a pickup time and max amount.

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?

Specific verb ("inspect") plus resource ("cart") and the exact payload returned (products, quantities, combo choices), so it is clearly a read of the current cart state rather than a mutation. It does not name the sibling tools it differs from (cart_add_simple, cart_add_configured, checkout_quote), leaving that inference to the agent.

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 wording "currently selected" (check cart contents before checkout), but there is no explicit guidance on when to call this versus cart_add_* or checkout_quote, nor any stated prerequisite such as authenticating the account first. The agent must infer the workflow position.

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