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

Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false and openWorldHint=true; the description adds real context beyond them — payment happens on Stripe's page and 'nothing is charged by this tool,' and prices are authoritative from the store rather than the request. It does not cover retry/idempotency behavior or link expiry, which keeps this from a 5.

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?

Four short sentences, front-loaded with the action, then the precondition, then the pay-flow behavior, then the pricing rule. No filler or repetition.

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 two-parameter creation tool with no output schema, the description covers preconditions and side-effect boundaries well. The notable gap is the return value — it implies a link exists but never states that the response contains the URL to hand to the shopper.

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 coverage is 50%: only 'store' is documented ('The store's slug'), leaving productId and quantity undescribed. The description helps by saying prices are not passed in the request and that quantities are shopper-confirmed, but it never explains where productId comes from or validates quantity semantics, so it only partly compensates.

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?

States a specific verb and resource ('Create a secure Stripe checkout link for products from one GYSM store') and scopes it to a single store, which distinguishes it from catalog/shop-discovery siblings like find_stores or get_store.

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?

Gives an explicit precondition: 'Only call it after the shopper has confirmed the items and quantities.' It does not name an alternative tool or state when not to use it, but the pre-call gate is clear enough to guide invocation.

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