# Reference — ADRs and Guides

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## Architecture Decision Records

| ADR | Date | Title | Status |
|-----|------|-------|--------|
| [2026-04-29-http-polling-no-websocket](adrs/2026-04-29-http-polling-no-websocket.md) | 2026-04-29 | HTTP polling instead of WebSocket | Accepted |
| [2026-04-29-openai-structured-output](adrs/2026-04-29-openai-structured-output.md) | 2026-04-29 | OpenAI structured JSON output for copy generation | Accepted |
| [2026-04-29-system-prompt-immutable-versioning](adrs/2026-04-29-system-prompt-immutable-versioning.md) | 2026-04-29 | Immutable system prompt versioning for FCA audit | Accepted |

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## RAG Corpus Documents

Located in `rag-corpus/` — these `.docx` files are embedded at deploy time and used to inject FCA compliance context into copy generation:

| Document | Content |
|----------|---------|
| `Consumer Duty summary.docx` | FCA Consumer Duty principles and requirements summary |
| `Consumer Understanding.docx` | Guidance on consumer-facing communications clarity |
| `Our Regulators and developing marketing material Chatai.docx` | Regulatory guidelines for Barclays marketing material |

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## Key Design Decisions (not in ADRs)

| Decision | Rationale |
|----------|-----------|
| DAM mock mode when `ADOBE_DAM_API_BASE_URL` is empty | Enables full UI development without DAM credentials |
| pgvector for both RAG and icon matching | Single DB for all similarity search — no separate vector store |
| RQ + Redis instead of Celery | Simpler setup for a single-server deployment |
| WeasyPrint for PDF | Renders HTML/CSS to PDF; banner HTML reuses the same rendering logic as the preview |
| `pair_id` UUID on BannerVariant | Groups all format variants from the same copy set for coherent display |
| Journey store with 2-hour TTL | Prevents stale banner-set links from surfacing in the stepper after session gap |