docs/FRONTEND_FALLBACKS.md

Frontend Fallback Behavior (Phase 5)

Overview

The UI uses Next.js /api/* route handlers as a proxy layer to the FastAPI backend.
If the backend is unavailable, these routes return safe defaults so the UI remains usable.

Proxy Routes (Next.js)

All routes forward to API_CONFIG.baseUrl (NEXT_PUBLIC_API_URL, default http://localhost:8000).

Search

• POST /api/search
• POST /api/search/hybrid
• Fallback: empty results with metadata stubs

Agents

• POST /api/agents/generate
• POST /api/agents/validate
• POST /api/agents/rank
• POST /api/agents/workflow
• Fallback: empty payloads with mock: true flags (where applicable)

Explorer

• GET /api/explorer/embeddings
• Fallback: 503 + empty points

Ingestion

• POST /api/ingest/pubmed
• POST /api/ingest/uniprot
• POST /api/ingest/chembl
• POST /api/ingest/all
• GET /api/ingest/jobs/{job_id}
• Fallback: 503 + error message

UI Empty‑State Handling

• Visualization page shows a “No points to display” message until a search runs.
• Workflow page shows “Run workflow to see results” until execution completes.

Recommendation

For demos, keep the FastAPI backend running to ensure real data/embeddings are shown.