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PROJECT DEEP DIVE

AI quote and invoice agent - Suite

Personal project · SME financial operations · Claude API, Supabase, Express 5

Situation

SMEs spend disproportionate time on quoting and invoicing — manual entry, no audit trail, VAT errors, no multi-tenant isolation. Existing tools require training.

What I built

A chat-first financial operations assistant where Claude plans the operation, typed handlers execute it, and all maths (totals, VAT) stays deterministic on the backend — not left to the model. Tenant isolation is enforced at the database level through JWT-scoped Supabase clients and row-level security, not application logic.

Result

Faster quote/invoice creation , a business owner describes work in natural language and gets a VAT-correct, PDF-ready quote or invoice. Each tenant's data is isolated by design, not by trust.

Architecture Diagram

Architecture flow

React Chat UI

Natural-language command input and artifact rendering.

Express /api/agent

JWT-authenticated chat endpoint and session persistence.

runAgent Loop

Bounded tool-use iterations with zod argument validation.

Domain Tool Handlers

Clients/templates/quotes/invoices/PDF deterministic operations.

Supabase + RLS

Tenant-isolated system of record with controlled number allocation.