Select Cart Items

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

The description clearly discloses that this operation overwrites the ticked cart selection, which is more informative than the annotations alone. It aligns with destructiveHint=true and idempotentHint=true, and no contradiction exists.

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 short sentences with no wasted words. The primary usage is front-loaded, and the parameter modes are presented compactly in the second sentence.

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 three-parameter tool with annotations and an output schema, the description is nearly complete. Minor ambiguity remains about whether the modes are mutually exclusive and what happens if no argument is passed, but these are not significant given the schema constraints.

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 0%, so the description must and does compensate by explaining the three usage forms: exact item_names, all=true, and none=true. The word 'exact' adds useful parameter semantics beyond the raw 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 ('overwrite') and resource ('live cart lines ticked for checkout'), making the tool's purpose unmistakable. It is clearly differentiated from sibling cart tools like add_to_cart or get_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 gives explicit invocation modes: exact item_names, all=true, or none=true. It implies this replaces the current selection, but it does not explicitly state when not to use this tool or name a specific alternative for adding/removing items.

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