Carts Get

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

Annotations already declare readOnly, idempotent, non-destructive, openWorld, so the safety profile is covered. The description adds genuine context beyond that: the HTTP verb/path, the required OAuth scope (read_orders), and the pinned API version 2025-03, which matters for behavior stability. It stops short of describing pagination or error conditions (e.g. cart not found / expired).

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?

Four short lines, front-loaded with the purpose followed by the endpoint, scope, and version. Every line carries usable information for an API wrapper; the only mild redundancy is the HTTP line restating the verb already in the first sentence.

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 read-only getter with full schema coverage and four annotations, this is close to self-sufficient: method, path, scope, and version are all present. The one remaining gap is that with no output schema, 'state and contents' is the only hint at the return payload, so an agent can't predict the shape of the cart object.

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 100%, so the ID, fields projection, and response_format enum are fully documented in the schema itself. The description adds no parameter-level meaning (no format for id, no guidance on when to use fields). Baseline 3 applies when the schema carries the burden.

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 and resource ('Get the state and contents of an active cart') with a scope qualifier ('active'), which is more than a restatement of the title. It doesn't explicitly contrast with the cart-related siblings (carts_delete_line_item, carts_delete_coupon), but those are obviously mutating operations whose names diverge enough that confusion is unlikely.

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 — retrieve a cart by ID — and the 'Required scope: read_orders' line gives a real prerequisite. However, there is no statement of when to prefer this over e.g. abandoned_checkouts_get or orders_get, and no note on what to do when a cart is no longer active. Adequate but not guiding.

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