add_to_cart

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

The description provides context beyond the tool name by explaining that the product ID comes from search_product. However, with no annotations, it doesn't disclose side effects like what happens if the product is already in the cart or whether a cart must exist, leaving the agent partially in the dark about behavioral outcomes.

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?

Two short, front-loaded sentences communicate the purpose and a critical prerequisite with no filler. Perfectly concise.

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 simple two-parameter tool with full schema coverage, the description is nearly complete. It names the action, the key parameter source, and with the sibling list, provides enough context for an agent to select and invoke the tool. The only gap is behavior on conflict, but this is a minor omission given the tool's simplicity.

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 schema already fully describes both parameters (product_id and quantity) with clear descriptions. The tool description merely restates the product_id source, adding no new parameter-specific information. According to the baseline for high schema coverage, this is a 3.

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 'Ajoute un produit au panier' (adds a product to the cart), which is a specific verb and resource. It also references 'search_product' to obtain the product ID, distinguishing it from cart-related siblings like remove_from_cart or update_quantity.

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?

It explicitly tells the agent to use the ID returned by search_product, implying a prerequisite search step. However, it doesn't explicitly state when not to use this tool (e.g., for quantity updates vs. adding new items), so it gets a 4 rather than 5.

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