Create Checkout invoice

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

The description discloses the core side effect (creates an invoice), the return value (hosted payment URL), and an important behavioral constraint (payment methods come from the merchant dashboard, not from parameters). This adds meaningful context beyond the annotations, which only indicate readOnly, idempotent, and destructive hints are all false.

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 two sentences with no filler. The primary action and return value are front-loaded, and the payment-method caveat is included compactly.

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 create operation with a 100%-covered schema, an output schema, and non-destructive annotations, the description and schema together give an agent everything needed to invoke the tool correctly. The key operational fact—that payment methods come from the merchant dashboard—is explicitly stated.

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 the schema already documents every parameter, including the minimum amount and field purposes. The description adds no new parameter-level meaning beyond stating that the invoice is in USD and that payment methods are dashboard-controlled.

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 states a specific verb and resource: 'Create a FinCobra Checkout invoice in USD' and clearly names the return value ('hosted payment URL'). This distinguishes it from sibling tools like get_invoice and list_sources, which are retrieval operations.

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 clearly implies this tool is for creating checkout invoices and explains that payment methods are controlled by the merchant dashboard rather than caller input. It does not explicitly say 'use this instead of get_invoice', but the creation-versus-read distinction makes the intended use clear.

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