Create guest cart

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

No annotations are provided, so the description carries the full behavioral burden. It discloses the side effect (creating a new cart), the return value (cart_id), the required follow-up usage, and the intended call frequency ('once'). For a zero-input creation tool, this is a complete behavioral contract.

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 two sentences with no filler. It front-loads the core purpose, then immediately provides the return contract and usage guidance, making it highly scannable for an agent.

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 low complexity, absence of input parameters, and lack of output schema, the description supplies everything needed for correct invocation: what the tool does, what it returns, and how the result is used downstream. Nothing essential is missing.

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 tool takes zero parameters, so there is no parameter information for the description to add. The description appropriately focuses on the output contract instead, which meets the baseline for parameterless tools.

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 and resource: 'Start a new anonymous (guest) shopping cart.' It clearly distinguishes itself from siblings like search_products, add_to_cart, and view_cart by focusing on cart creation and naming its return value.

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 gives explicit usage context: 'Call this once at the start of a shopping session.' It also tells the agent that the returned cart_id must be passed to add_to_cart and view_cart. It does not explicitly state when not to use it, such as for logged-in users, but 'anonymous (guest)' makes that implication clear.

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