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

With no annotations provided, the description must carry the full burden of behavioral disclosure. It only states 'Requires auth', which is a modest precondition. It does not explain side effects (e.g., initiating a payment, creating a Stripe session, charging the user), return format, or any redirect behavior. This is insufficient for a mutation-like purchase tool.

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 extremely concise: two short sentences that deliver clear information without any filler. The key action is front-loaded and the auth note is a useful exception. Every word earns its place.

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?

The tool is a purchase initiation but the description lacks essential context. It does not disclose what the Stripe checkout entails, whether it returns a URL or session ID, or any error conditions. With no output schema, the agent has no idea what the response looks like. The single param is trivial, but the behavioral and return context are incomplete.

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 has one parameter (listing_id) with zero description coverage. The description loosely connects it to 'a listing' but does not explain how to obtain it, its format, or its role in the checkout process. The parameter name is self-explanatory, but the description adds minimal semantic value beyond the 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 clearly states the action (Start Stripe checkout) and the target (a listing). It implies a payment-related operation for a specific listing. However, it does not explicitly distinguish itself from similar siblings like headless_checkout or quick_purchase, which could also relate to checkout/purchase flows.

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 no guidance on when to use this tool versus alternatives. It only mentions that authentication is required, which is a prerequisite but not usage context. There is no mention of scenarios where this tool is preferred over headless_checkout or quick_purchase.

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