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

With no annotations, the description carries the full burden and does disclose the fee split (HOBO takes 25%) and the post-webhook lifecycle step, which is genuine behavioral context. It omits authorization requirements, refund/expiry behavior, and what a failed webhook means — notable gaps for a payment 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?

Three tight sentences, front-loaded with the core action followed by economics, follow-up step, and the free-path alternative. No filler.

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?

A payment-initiating tool with no annotations and no output schema needs the description to do more. The money-flow and webhook hint are helpful, but auth needs, failure handling, and idle-checkout behavior are absent for an operation of this complexity.

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 0% for the single product_id parameter, and the description never explains its expected value or format. 'Paid marketplace product' gives only the loosest hint that product_id identifies a product, so the description fails to compensate for the coverage gap.

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 ('Create') plus resource ('one-time Stripe Checkout') and scope ('for a paid marketplace product'). It clearly separates itself from claim_free_download (free) and, by implication, create_usdc_invoice (alternate payment rail).

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?

Explicitly routes free downloads to claim_free_download and describes the post-purchase flow ('call get_order after the verified webhook'). It does not, however, state when to prefer this over create_usdc_invoice, which is a plausible sibling alternative for paid flows.

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