diff --git a/README.md b/README.md
index b6d7da7..2df88c1 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,185 @@
-# ML
+# ML Repo — Architecture and External RAG Server Design (for Ollama/Open WebUI)
 
-My openWebUI/searxng configs, plugins, RAG server, as well as a custom program that runs the AI's code in isolated Docker containers
\ No newline at end of file
+My openWebUI/searxng configs, plugins, RAG server, as well as a custom program that runs the AI's code in isolated Docker containers
+
+*Last updated: 2025-09-10*
+
+---
+
+## Summary :3
+
+This repository wires together a local AI stack built around **Open WebUI**, **Ollama**, **SearxNG**, and two custom utilities: a **code runner** (executes model-generated code inside sandboxed containers) and a **headless research browser UI**. The current compose setup already gives you working RAG (retrieval-augmented generation) **inside Open WebUI** without needing a separate RAG service.
+
+---
+
+## Repo map and how each piece fits
+
+```sh
+.
+├─ docker-compose.yml
+├─ searxng.yml                  # searxng settings; defaults, json+html enabled; not a public instance
+├─ cloudflared-tunnel-config.yml # cloudflare tunnel routing to ollama, openwebui, and tools
+├─ README.md
+├─ LICENSE                      # apache-2.0
+│
+├─ rag-server/
+│  ├─ Dockerfile                # Runs the file that does the RAG stuff
+│  └─ index.tsx                 # Does the RAG stuff
+│
+├─ browser/
+│  └─ Dockerfile                # builds browser-use/web-ui (playwright chromium) on :7788
+|
+└─ coderunner/
+   ├─ Dockerfile                # bun-based service that exposes an OpenAPI tool for sandboxed code exec
+   ├─ index.ts                  # the server; integrates with Open WebUI as a tool via /openapi.json
+   └─ package.json              # @types/node only (dev) to feed the OCD
+```
+
+### Open WebUI (in `docker-compose.yml`)
+
+* purpose: chat UI + orchestration layer; **includes a built-in knowledge base + RAG** with chunking, embedding, search, and prompt templating.
+* notable: backed by Postgres in this compose. exposes `4000:8080`.
+* storage: a docker volume `open-webui:` holds app data; Postgres uses `pgdata:`.
+
+### Postgres (in `docker-compose.yml`)
+
+* purpose: persistence for Open WebUI features (users, knowledge, etc.). health-checked with `pg_isready`.
+
+### SearxNG (in `docker-compose.yml` + `searxng.yml`)
+
+* purpose: metasearch engine used by Open WebUI tools/agents for live web lookups.
+* config highlights: `use_default_settings: true`, `public_instance: false`, `limiter: false`; formats: `html` and `json`.
+
+### Coderunner service (`coderunner/`)
+
+* **what it is:** a small HTTP server (Bun runtime) that executes pure source code in short-lived, sandboxed containers.
+* **why it exists:** lets Open WebUI tools run code safely with tight resource limits (no network, read-only fs, cgroup limits, `--cap-drop=ALL`, `no-new-privileges`).
+* **integration contract:** exposes an **OpenAPI schema at `/openapi.json`** and a single POST `/execute` endpoint. Open WebUI can import this as a **tool server**.
+* **security posture:** pulls allow-listed base images (gcc, python, node, bun, etc.), mounts only a tmpfs workdir, times out jobs ≈25s, and runs with non-root uid/gid. the container has access to the host’s docker socket *only* to run the sandbox containers.
+
+### Browser-use web-ui (`browser/`)
+
+* purpose: “autonomous” research browser UI (chromium via playwright), reachable on `:7788`.
+* built from upstream `browser-use/web-ui` repo, with python deps and browsers installed in the image.
+
+### Cloudflared tunnel (`cloudflared-tunnel-config.yml`)
+
+* maps hostnames (like `mlep.domain.com` for Ollama, `owebui.domain.com` for Open WebUI, and a `tools` host) to the internal services. useful for private, authenticated access without public inbound ports.
+
+---
+
+## Why you currently **don’t** need an external RAG server
+
+Open WebUI ships with first-class **knowledge / RAG** support: add files/URLs, it chunks + embeds, indexes, retrieves, and automatically **prefixes retrieved context** to the model prompt using a RAG template. for lightweight to mid-sized corpora and single-user/small-team usage, that’s often all you need.
+
+**Stay with built-in RAG if most of these are true:**
+
+* total corpus is ≤ \~100k chunks and grows slowly.
+* single user or small team (no multi-tenant isolation needed).
+* no special retrieval logic (hybrid lexical+semantic, rerankers, metadata filters) beyond what Open WebUI provides.
+* tolerance for “UI-managed” knowledge; you don’t need programmatic ingestion pipelines or job queues.
+
+## When an external RAG server makes sense
+
+Adopt a decoupled RAG service when you need one or more of:
+
+* **bigger data / throughput**: millions of chunks, higher QPS, horizontal scaling.
+* **advanced retrieval**: custom chunkers, hybrid search (bm25 + vector), **reranking**, time-decay, per-tenant filters, embeddings A/B, or multi-modal (image/audio) retrieval.
+* **programmatic ingestion**: CI-driven pipelines from git/docs/confluence/S3; delta updates; background jobs.
+* **governance / isolation**: strict multi-tenant separation, PII retention controls, audit trails.
+* **interoperability**: a clean HTTP API and OpenAPI so other apps (beyond Open WebUI) can reuse your index.
+
+---
+
+## External RAG Server — Design and Reference Implementation
+
+This is a small, dependency-light service designed to run with **Bun** and integrate with both **Ollama** and **Open WebUI**.
+
+### Goals
+
+* minimal moving parts; runs fine on a single host.
+* uses Ollama for **embeddings** and **chat**.
+* supports **collections**, **upserts**, **queries**, and an opinionated `/chat` that does retrieve-then-generate.
+* ships an **OpenAPI** so Open WebUI can import it as a tool server.
+* default in-memory store (persisted to JSON) for simplicity; optional adapters for vector DBs later.
+
+### API surface
+
+* `GET /openapi.json` – schema for tool integration.
+* `POST /collections` – create a logical collection `{ name }`.
+* `GET /collections` – list collections.
+* `POST /upsert` – `{ collection, items:[{ id?, text, metadata? }] }`; chunks+embeds text and stores vectors.
+* `POST /query` – `{ collection, query, topK?=5, where? }` --> nearest chunks with scores.
+* `POST /chat` – `{ collection, query, topK?=5, model?, embedModel? }` --> runs RAG and calls Ollama chat, returns the answer + citations.
+
+### Storage Strategy
+
+* **default:** in-memory + JSON file on disk (`./data/rag.json`). good for dev/small usage.
+* **plug-in adapters:** swap in Qdrant, SQLite-Vec, pgvector, Weaviate, etc., without changing the HTTP API.
+
+---
+
+### Add to `docker-compose.yml`
+
+```yaml
+  rag:
+    build:
+      context: ./rag-server
+      dockerfile: Dockerfile
+    environment:
+      OLLAMA_BASE: "http://mlep.domain.com:11434"
+      OLLAMA_CHAT_MODEL: "llama3.1"
+      OLLAMA_EMBED_MODEL: "nomic-embed-text"
+    volumes:
+      - rag_data:/app/data
+    networks:
+      - internal
+    restart: unless-stopped
+
+volumes:
+  rag_data:
+```
+
+> if you already expose services via cloudflared, add another hostname mapping to the `rag` container (`- hostname: rag.domain.com -> service: http://rag:8788`).
+
+---
+
+## Wiring the RAG server into Open WebUI and Ollama
+
+### 1. Pull models
+
+* `ollama pull nomic-embed-text` (embeddings)
+* `ollama pull llama3.1` (chat)
+
+### 2. Expose the OpenAPI to Open WebUI as a **tool server**
+
+* in Open WebUI --> **settings --> tools** --> **add tool server**
+* paste the url for the cloudflared hostname
+* you’ll now see tool functions like `listCollections`, `createCollection`, `upsert`, `query`, `chat` available to the assistant
+
+### 3. Usage pattern inside a chat
+
+* to build a knowledge base, call the `createCollection` and `upsert` tools with your documents
+* to answer, call `chat` which performs retrieve-then-generate against your chosen collection
+
+---
+
+## FAQ — Built-in vs. External RAG
+
+**Q: will Open WebUI’s built-in RAG conflict with this server?**
+no — you can use either, or both. Open WebUI’s knowledge base is great for ad-hoc use. this service is for programmatic/control-plane needs or when you outgrow the UI’s storage/retrieval.
+
+**Q: how do enforce tenant isolation?**
+use one collection per tenant and never mix. for stronger guarantees, run separate RAG instances or choose Qdrant with per-collection access control.
+
+**Q: how can use my chunker/reranker?**
+yes. place them ahead of `/upsert` and `/query` respectively, or add endpoints like `/rerank` and `/embed` to experiment.
+
+**Q: can this call OpenAI-compatible endpoints instead of native Ollama?**
+Ollama exposes an experimental OpenAI-compatible API. you can add a thin client if you already point tools at `/v1/chat/completions`.
+
+---
+
+## License
+
+This write-up and reference code are provided under the same **Apache-2.0** terms as the repository.
diff --git a/rag-server/Dockerfile b/rag-server/Dockerfile
new file mode 100644
index 0000000..4aaf98c
--- /dev/null
+++ b/rag-server/Dockerfile
@@ -0,0 +1,12 @@
+# syntax=docker/dockerfile:1
+FROM oven/bun:1.2.2-alpine
+
+WORKDIR /app
+
+COPY index.ts ./index.ts
+
+ENV PORT=8788
+
+EXPOSE 8788
+
+CMD ["bun","run","index.ts"]
\ No newline at end of file
diff --git a/rag-server/index.ts b/rag-server/index.ts
new file mode 100644
index 0000000..64ce2be
--- /dev/null
+++ b/rag-server/index.ts
@@ -0,0 +1,289 @@
+import { serve } from "bun";
+import fs from "node:fs";
+import path from "node:path";
+
+// types
+interface Chunk {
+	id: string;
+	text: string;
+	metadata?: Record<string, unknown>;
+	vector: number[];
+}
+
+interface Collection {
+	name: string;
+	chunks: Chunk[];
+}
+
+interface OllamaChatMessage {
+	role: "system" | "user" | "assistant";
+	content: string;
+}
+
+interface OllamaChatRequest {
+	model?: string;
+	messages: OllamaChatMessage[];
+	stream?: boolean;
+}
+
+interface OllamaChatResponse {
+	message?: OllamaChatMessage;
+	[k: string]: unknown;
+}
+
+interface UpsertInputItem {
+	text: string;
+	metadata?: Record<string, unknown>;
+}
+
+interface OpenAPIObject {
+	openapi: string;
+	info: { title: string; version: string };
+	paths: Record<string, unknown>;
+}
+
+// env
+const PORT: number = Number(process.env.PORT || 8788),
+	HOST: string = process.env.HOST || "0.0.0.0",
+	OLLAMA_BASE: string = process.env.OLLAMA_BASE || "http://localhost:11434",
+	OLLAMA_CHAT_MODEL: string = process.env.OLLAMA_CHAT_MODEL || "llama3.1",
+	OLLAMA_EMBED_MODEL: string = process.env.OLLAMA_EMBED_MODEL || "nomic-embed-text",
+	DATA_DIR: string = process.env.DATA_DIR || path.resolve("./data"),
+	SNAPSHOT: string = path.join(DATA_DIR, "rag.json");
+
+// in-memory db
+const db: Map<string, Collection> = new Map();
+
+// util: smol json persistence
+function ensureDirs(): void {
+	if (!fs.existsSync(DATA_DIR)) fs.mkdirSync(DATA_DIR, { recursive: true });
+}
+
+// you can probably guess
+function loadSnapshot(): void {
+	try {
+		ensureDirs();
+		if (fs.existsSync(SNAPSHOT)) {
+			const raw = fs.readFileSync(SNAPSHOT, "utf8");
+			const obj = JSON.parse(raw || "{}") as Record<string, Collection>;
+			for (const [name, value] of Object.entries(obj)) db.set(name, value);
+		}
+	} catch (e) {
+		console.warn("failed to load snapshot:", e);
+	}
+}
+
+// you can probably guess 2
+function saveSnapshot(): void {
+	try {
+		ensureDirs();
+		const obj = Object.fromEntries(db.entries());
+		fs.writeFileSync(SNAPSHOT, JSON.stringify(obj, null, 2));
+	} catch (e) {
+		console.warn("failed to save snapshot:", e);
+	}
+}
+
+loadSnapshot();
+
+// basic text splitter (recursive by punctuation, then by length)
+function chunkText(text: string, maxLen = 800): string[] {
+	const parts = text
+		.split(/\n{2,}/g)
+		.flatMap(p => p.split(/(?<=[.!?])\s+/g))
+		.flatMap(s => s.length > maxLen ? s.match(new RegExp(`.{1,${maxLen}}`, "g")) || [] : [s])
+		.map(s => s.trim())
+		.filter(Boolean);
+	return parts;
+}
+
+// cosine similarity
+function dot(a: number[], b: number[]): number { let s = 0; for (let i = 0; i < a.length; i++) s += (a[i] || 0) * (b[i] || 0); return s; }
+function norm(a: number[]): number { return Math.sqrt(dot(a, a)); }
+function cosineSim(a: number[], b: number[]): number { const d = dot(a, b), n = norm(a) * norm(b) || 1; return d / n; }
+
+// call ollama embeddings
+async function embedAll(texts: string[]): Promise<number[][]> {
+	const primary = await fetch(`${OLLAMA_BASE}/api/embed`, {
+		method: "POST",
+		headers: { "content-type": "application/json" },
+		body: JSON.stringify({ model: OLLAMA_EMBED_MODEL, input: texts })
+	});
+
+	if (primary.ok) {
+		const j: { embeddings: number[][] } = await primary.json();
+		return j.embeddings;
+	}
+
+	const results: number[][] = [];
+	for (const t of texts) {
+		const r = await fetch(`${OLLAMA_BASE}/api/embeddings`, {
+			method: "POST",
+			headers: { "content-type": "application/json" },
+			body: JSON.stringify({ model: OLLAMA_EMBED_MODEL, prompt: t })
+		});
+
+		if (!r.ok) throw new Error(`embed failed: ${r.status}`);
+
+		const j: { embedding: number[] } = await r.json();
+		results.push(j.embedding);
+	}
+	return results;
+}
+
+// call ollama chat/generate with retrieved context
+async function ollamaChat(req: OllamaChatRequest): Promise<OllamaChatResponse> {
+	const res = await fetch(`${OLLAMA_BASE}/api/chat`, {
+		method: "POST",
+		headers: { "content-type": "application/json" },
+		body: JSON.stringify({ model: req.model || OLLAMA_CHAT_MODEL, messages: req.messages, stream: req.stream })
+	});
+
+	if (!res.ok) throw new Error(`ollama chat failed: ${res.status}`);
+	const j: OllamaChatResponse = await res.json();
+
+	return j;
+}
+
+// openapi for open webui tool integration
+const OPENAPI: OpenAPIObject = {
+	openapi: "3.1.0",
+	info: { title: "RAG Server (Ollama)", version: "1.0.0" },
+	paths: {
+		"/collections": {
+			get: { operationId: "listCollections" },
+			post: { operationId: "createCollection" }
+		},
+		"/upsert": { post: { operationId: "upsert" } },
+		"/query": { post: { operationId: "query" } },
+		"/chat": { post: { operationId: "chat" } }
+	}
+};
+
+// tiny router
+async function json<T = any>(req: Request): Promise<T> { try { return await req.json() as T; } catch { return {} as T; } }
+function sendJson(_res: unknown, status: number, obj: unknown): Response {
+	return new Response(JSON.stringify(obj), { status, headers: { "content-type": "application/json; charset=utf-8" } });
+}
+
+async function handleCollections(req: Request): Promise<Response> {
+	if (req.method === "GET") {
+		return sendJson(null, 200, { collections: Array.from(db.keys()) });
+	}
+
+	if (req.method === "POST") {
+		const body = await json<{ name?: string }>(req),
+			name = String(body?.name || "").trim();
+
+		if (!name) return sendJson(null, 400, { error: "name required" });
+		if (!db.has(name)) db.set(name, { name, chunks: [] });
+
+		saveSnapshot();
+		return sendJson(null, 200, { ok: true });
+	}
+
+	return new Response("not found", { status: 404 });
+}
+
+async function handleUpsert(req: Request): Promise<Response> {
+	const body = await json<{ collection?: string; items?: UpsertInputItem[] }>(req),
+		collection = String(body?.collection || "").trim(),
+		items: UpsertInputItem[] = Array.isArray(body?.items) ? body.items : [];
+
+	if (!collection) return sendJson(null, 400, { error: "collection required" });
+	if (!db.has(collection)) db.set(collection, { name: collection, chunks: [] });
+
+	const col = db.get(collection)!,
+		chunksToIndex: { text: string; metadata?: Record<string, unknown>; _id: string }[] = [];
+
+	for (const it of items) {
+		const parts = chunkText(String(it.text || ""));
+		for (const p of parts) chunksToIndex.push({ text: p, metadata: it.metadata || {}, _id: crypto.randomUUID() });
+	}
+
+	const vecs = await embedAll(chunksToIndex.map(x => x.text));
+	for (let i = 0; i < chunksToIndex.length; i++) {
+		const item = chunksToIndex[i],
+			doc: Chunk = { id: item._id, text: item.text, metadata: item.metadata, vector: vecs[i] };
+
+		col.chunks.push(doc);
+	}
+
+	saveSnapshot();
+	return sendJson(null, 200, { ok: true, indexed: chunksToIndex.length });
+}
+
+async function handleQuery(req: Request): Promise<Response> {
+	const body = await json<{ collection?: string; query?: string; topK?: number }>(req),
+		collection = String(body?.collection || "").trim(),
+		query = String(body?.query || "").trim(),
+		topK = Number(body?.topK || 5);
+
+	if (!collection || !query) return sendJson(null, 400, { error: "collection and query required" });
+
+	const col = db.get(collection);
+	if (!col) return sendJson(null, 404, { error: "collection not found" });
+
+	const [qvec] = await embedAll([query]),
+		scored = col.chunks.map((c) => ({ c, score: cosineSim(qvec, c.vector) }))
+			.sort((a, b) => b.score - a.score)
+			.slice(0, topK)
+			.map(x => ({ id: x.c.id, text: x.c.text, metadata: x.c.metadata, score: x.score }));
+	return sendJson(null, 200, { matches: scored });
+}
+
+async function handleChat(req: Request): Promise<Response> {
+	const body = await json<{ collection?: string; query?: string; topK?: number; model?: string }>(req),
+		collection = String(body?.collection || "").trim(),
+		query = String(body?.query || "").trim(),
+		topK = Number(body?.topK || 5),
+		model = body?.model || OLLAMA_CHAT_MODEL;
+
+	if (!collection || !query) return sendJson(null, 400, { error: "collection and query required" });
+
+	const col = db.get(collection);
+	if (!col) return sendJson(null, 404, { error: "collection not found" });
+
+	const [qvec] = await embedAll([query]),
+		matches = col.chunks.map((c) => ({ c, score: cosineSim(qvec, c.vector) }))
+			.sort((a, b) => b.score - a.score)
+			.slice(0, topK);
+
+	const context = matches.map((m, i) => `[[doc ${i + 1} score=${m.score.toFixed(3)}]]\n${m.c.text}`).join("\n\n"),
+		system: string = `you are a helpful assistant. use ONLY the provided context to answer. if the answer isn't in the context, say you don't know. cite as [doc N].`,
+		user: string = `question: ${query}\n\ncontext:\n${context}`;
+
+	const out = await ollamaChat({ model, messages: [{ role: "system", content: system }, { role: "user", content: user }], stream: false });
+	return sendJson(null, 200, {
+		answer: out?.message?.content || "",
+		citations: matches.map((m, i) => ({ id: m.c.id, score: m.score, text: m.c.text }))
+	});
+}
+
+const pickFunc = (pathname: string) => {
+	switch (pathname) {
+		case "/collections":
+			return handleCollections;
+		case "/upsert":
+			return handleUpsert;
+		case "/query":
+			return handleQuery;
+		case "/chat":
+			return handleChat;
+		default:
+			return undefined;
+	}
+}
+
+const server = serve({
+	port: PORT,
+	hostname: HOST,
+	fetch: async (req: Request): Promise<Response> => {
+		const u = new URL(req.url);
+		if (req.method === "GET" && u.pathname === "/") return new Response("ok");
+		if (req.method === "GET" && u.pathname === "/openapi.json") return sendJson(null, 200, OPENAPI);
+		return pickFunc(u.pathname)?.call(req) || new Response("not found", { status: 404 });
+	}
+});
+
+console.log(`[rag] listening on http://${HOST}:${PORT}`);
\ No newline at end of file