validate_checkout_summary

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 need for an authenticated session and that it submits a device fingerprint ID for fraud prevention, which adds context. However, it does not disclose whether the tool mutates state (e.g., creates a checkout session) or is read-only, nor does it describe side effects like updating the cart or invalidating previous steps.

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 a single paragraph with two sentences, front-loading the main purpose and then listing outputs and usage context. It is concise and avoids redundancy, though it could be slightly more structured with bullet points for the output list, but it remains efficient.

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 has 2 parameters, no output schema, and no annotations, the description does a good job explaining the purpose, required authentication, and what the response contains. It lacks details on error conditions or side effects, but for a validation step it is reasonably complete. The mention of 'requires an authenticated session' is crucial and present.

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 provides 100% coverage for both parameters, including examples and purpose. The description adds minimal extra meaning beyond the schema, only mentioning that basket_service_type is part of the URL path and that deviceFingerPrintId is for fraud prevention, which is already in the schema. Baseline 3 is appropriate.

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 the tool validates the checkout summary for a specific basket service type on Carrefour France, and lists the key outputs (cart state, checkout step, store context, workflow steps, warnings, checkout links). It distinguishes itself from siblings like validate_checkout_slot and submit_checkout_payment by focusing on the summary validation step before payment.

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 provides clear context: it is useful for initiating or confirming the checkout summary step before proceeding to payment. It also notes the requirement of an authenticated session. However, it does not explicitly state when not to use it or mention alternatives like validate_checkout_slot, though the sibling list implies such alternatives exist.

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