Deterministic Policy Enforcement, GraphRAG Rule Retrieval, and Statutory Grounded Adjudication for Financial Networks.
- 📚 Digitized Rule Knowledge Base: Digitized coverage of all 21 American Express Chargeback Reason Codes and 6 Retrieval Codes with statutory requirements, evidence obligations, and filing constraints.
- 🛡️ 6-Step Deterministic Policy Gate: Enforces statutory filing windows (120-day standard, 540-day delivery extension) and hard exclusion reroutes (e.g., 4536 invalid authorization → 4521 reroute).
- 🤖 ML Narrative Classifier & Ambiguity Guard: TF-IDF + Logistic Regression model trained on dispute claim narratives with top-k margin confidence ranking and ambiguity detection.
- ⚖️ Fairness-Weighted Evidence Engine: Automatic evidence matching with OR-gate rule evaluation. Low-confidence cases (<0.80) or legal exceptions (Reason Code 4754) automatically route to the Reviewer Escalation Queue.
- 📜 Dual-Register Explainability: Generates plain-English resolution summaries for cardholders alongside technical, clause-cited breakdown reports with downloadable SHA-256 cryptographic audit PDFs.
- 👤 Multi-Persona RBAC Portal: Dedicated workflows for Card Members (dispute intake), Merchants (evidence rebuttal checklist), and Human Reviewers (escalation queue & decision trace viewer).
| Layer | Technology |
|---|---|
| Frontend UI | React, Vite, Tailwind CSS v4, TanStack React Query, Axios, Lucide Icons |
| Backend API | Python 3.10+, FastAPI, Pydantic v2, Motor (Async MongoDB), PyJWT, Structlog |
| Database & Search | MongoDB (Primary Store), Neo4j (Graph Exclusions), Qdrant (Vector Embeddings) |
| Testing & Quality | Playwright (E2E Browser Tests), Vitest (Component Tests), Pytest (Backend Tests) |
| Containerization | Docker, Docker Compose |
- Node.js v18+ & npm
- Python 3.10+
- MongoDB, Neo4j, and Qdrant (or Docker)
# Navigate to backend directory
cd backend
# Create virtual environment & install dependencies
python -m venv venv
source venv/bin/activate # On Windows: .\venv\Scripts\activate
pip install -r requirements.txt
# Start FastAPI dev server
uvicorn app.main:app --reload --port 8000API documentation available at http://localhost:8000/docs.
# Navigate to frontend directory
cd frontend
# Install dependencies & start Vite dev server
npm install
npm run devApplication available at http://localhost:5173.
docker-compose up --build# Run Vitest Component Unit Tests
cd frontend
npx vitest run
# Run Playwright E2E Browser Journey Tests
npx playwright testLicensed under the MIT License.