InvoicePilot helps freelancers prepare and track invoices through chat. It extracts invoice details, asks for missing information, and creates a reviewable draft. FastAPI validates the draft and records a pending action; the model cannot call PayPal. After explicit human confirmation, the API can create and send invoices through PayPal Invoicing API v2 Sandbox. The default demo uses a deterministic parser and fictional local data. Optional Claude (Anthropic) mode provides structured invoice drafting. Live Sandbox execution requires credentials and has not been smoke-tested.