get_loyalty_cards

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

No annotations are provided, so the description carries the burden. It mentions the authentication requirement and that it returns card list with types, but does not disclose potential errors, side effects, or whether it is read-only. Without annotations, this is minimal but not misleading.

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 concise, a single sentence with an additional note on authentication. It is front-loaded with the action and subject, with no redundant filler. Slightly verbose with the parenthetical but acceptable.

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 simplicity (no parameters, no output schema), the description covers the essential purpose, return type, and authentication prerequisite. It could mention that it is read-only, but the overall completeness is adequate for a zero-parameter tool.

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 has zero parameters, and the schema has 100% coverage (empty properties). The description confirms no parameters are needed, and adds context about the return content (card numbers and types). Baseline for zero params is 4, and the description adds clarity.

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 it retrieves loyalty cards for the authenticated user on Carrefour France, and specifies it returns card numbers and types. It distinguishes itself from similar siblings like get_loyalty_balance and get_loyalty_coupon_dashboard by focusing on the list of cards, though not explicitly differentiating.

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 implies usage when displaying the user's loyalty cards, and notes the need for an authenticated session. However, it does not provide explicit when-to-use vs alternatives, such as when to use get_loyalty_balance or other loyalty-related tools.

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