Nexus

Nexus platform

About

Open-stack reference RAG skeleton: ingestion, Gemini embeddings stored in Postgres with pgvector, cosine retrieval, and citation-aware answers returned as structured JSON usable from the REST API and MCP.

Runtime models (env overrides)

Chat / JSON generation
gemini-2.5-flash
Vision OCR (PDF / image)
gemini-2.0-flash
Embeddings
gemini-embedding-001 · 768-dim vector column

Values shown reflect your environment at request time. Defaults live in lib/ai.ts when env vars are unset.

Chat response envelope

Version nexus.chat.v1 objects include:

  • text plain language string
  • markdown rich Markdown (GFM, KaTeX) with optional [[S1]] cite markers
  • sources[] chunk ids, filenames, similarity, excerpts
  • hallucination_flag when retrieval gate fails

Legacy fields answer and citations mirror text and sources for older clients.

Application stack

  • Next.js 14 App Router, TypeScript, Tailwind CSS
  • Prisma ORM on PostgreSQL with pgvector (IVFFlat cosine index via init route)
  • Google AI Studio: Gemini JSON chat, multimodal OCR, REST embedContent
  • Client rendering: react-markdown, remark-gfm, remark-math, rehype-katex
  • Optional MCP JSON-RPC surface at /api/mcp