taobao_add_to_cart

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

Annotations show readOnlyHint=false and destructiveHint=false. The description adds valuable behavioral context: it validates variant chips, uses the mtop.trade.addBag API with a fallback to button click, and states that confirm governs a gated write. It also explicitly lists actions it never performs (buy, checkout, etc.), exceeding annotation coverage.

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?

The description is a single paragraph but well-organized: purpose first, then behavior, then example. It is efficient but could be slightly shorter by removing the API detail. The example adds clarity.

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?

Given the tool's complexity and the presence of an output schema (not shown but noted), the description covers the core behavior, limitations, and an example. It omits prerequisites like login status and error handling, but these are reasonable gaps for an AI agent.

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 coverage is 0%, so the description must compensate. It explains options as 'one value per variant group' with an example, and describes confirm as gating a write. However, qty and product_url_or_id are not elaborated beyond their names and defaults, though they are straightforward.

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?

The description clearly states the tool's purpose: 'Stage one product+variant into the cart.' It uses specific verbs and resources, and distinguishes itself from buying, checking out, or paying, which sets it apart from siblings like taobao_track_orders or taobao_search.

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 description provides explicit context: 'Preview-only unless confirm=True (gated write)' and 'NEVER buys, checks out, pays, or picks an address — only stages into the cart.' It implies usage for adding items to cart, not for completing purchases, but does not directly compare with each sibling tool.

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