ls_create_checkout

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

Annotations already establish this is a mutation (readOnlyHint=false) and not idempotent. The description adds that it returns a URL and that it supports custom pricing, prefill, and customization, but it does not disclose side effects, auth requirements, or behavior around expiry/payment. This is acceptable but not rich.

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?

Three short sentences with the core action front-loaded. There is minor redundancy ('Create a new checkout URL' vs 'Returns a URL...') but no filler or irrelevant detail.

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?

With 12 parameters, a required storeId/variantId pair, and no output schema, the description gives a useful high-level summary but omits the exact response shape and any edge-case behavior. The schema covers parameter details, but the tool's output contract is only described as 'a URL'.

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 100%, so every parameter is individually documented. The description's mention of 'custom pricing, prefilled customer data, and checkout customization' only groups existing schema capabilities without adding new meaning beyond the schema. Baseline 3 applies.

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 opens with a specific verb and resource: 'Create a new checkout URL for a product variant,' and immediately clarifies the output (the purchase URL). This clearly distinguishes the tool from sibling read tools like ls_get_checkout and ls_list_checkouts.

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 use case is clear: you use this when you need to generate a checkout URL for a variant. However, the description never explicitly names alternatives or states when not to use the tool; the distinction from siblings is implied by the create verb rather than stated.

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