create_invoice_usd

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

Despite having no annotations, the description discloses the key non-obvious behavior: the invoice is denominated in satoshis but credited as USD. This is critical for user expectations and goes beyond a simple 'create invoice' statement. It lacks details about authentication, reversibility, or failure modes, but the core behavioral nuance is well communicated.

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 only two sentences and front-loads the action and subject. It avoids redundant phrasing and every sentence contributes substantive information: the creation action, currency-specific amount, and the satoshi-to-USD credit nuance. No fluff or 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?

For a tool with 5 parameters, no annotations, and no output schema, the description covers the core create-invoice behavior and a key conversion detail, but omits return value expectations, optional parameter meanings, and any operational constraints like expiry or amount limits. It is adequate for basic invocation but leaves gaps for a fully informed agent.

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 only 40% (amount and wallet_id have descriptions). The description adds meaning for 'amount' by specifying USD cents, and for 'wallet_id' indirectly via 'USD wallet ID' in the schema. However, it does not explain memo, expires_in, or external_id, and with low coverage the description should compensate more. Optional parameters remain ambiguous.

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 tool creates a Lightning invoice for receiving a specific USD amount in cents, and distinguishes it from sibling tools like create_invoice or create_invoice_no_amount by explicitly mentioning Stablesats and USD-centric behavior. The verb 'create' is specific and the resource ('Lightning invoice', 'USD cents') is well defined.

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 implies this tool is for USD-denominated invoices, providing context that it converts USD cents into a satoshi-denominated invoice. However, it does not explicitly contrast with sibling tools such as create_invoice or create_invoice_no_amount, nor does it state when to prefer this over alternatives. The usage context is clear but not exclusionary.

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