add_to_cart

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

With no annotations, the description must disclose effects, prerequisites, and side effects. It does not mention what happens if the item already exists, permission needs, or whether login is required.

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 very short (two sentences) and front-loaded with the main action, but could be slightly more informative without losing conciseness.

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?

Despite a simple tool and an existing output schema, the description omits crucial context like error scenarios, behavior on repeated item addition, and response details.

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 description should compensate for missing parameter documentation. It only restates quantity's default (already in schema) and says nothing about item_id.

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 explicitly states the action (Add) and target (item to the cart), clearly distinguishing it from siblings like remove_from_cart and check_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?

The description mentions quantity optionality but provides no explicit guidance on when to use this tool versus other cart operations, relying on tool name for context.

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