Add Product to Cart

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

Annotations already indicate mutation (readOnlyHint=false, idempotentHint=false), so the description adds limited but useful context by specifying the target as the user's live Lazada cart and framing the operation as additive. It does not disclose auth requirements or exact side effects, but the annotations carry the core behavioral burden.

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 sentence with no filler, front-loading the action and object. Every word earns its place.

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 two-parameter tool with a complete input schema and an output schema present, the description covers the essential operation and target context. It stops short of 5 only because it does not mention session/login preconditions or clarify behavior when the product already exists in the cart.

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 parameters are already well documented. The description's 'units' and 'one product' loosely align with quantity and url but do not add new semantic detail beyond the schema.

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 states a specific verb ('add'), a concrete resource ('the user's live Lazada cart'), and a clear scope ('units of one product'). This semantically distinguishes it from siblings like remove_from_cart, set_cart_quantity, and add_shortlist_to_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?

'Use this to...' gives a clear and direct context for when the tool applies. It does not explicitly mention when not to use it or name alternatives, but the usage intent is unambiguous given the sibling set.

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