ELELEM · Epoch Tour · Chile

From LLMs to Agentic Systems

A three-day workshop about understanding, not just doing: how language models actually work, what retrieval really does, what turns an LLM into an agent — and why these systems fail. Every lecture comes with a hands-on lab.

📅 Thu 22 – Sat 24 Oct 2026 📍 UdeC Campus Santiago · Marchant Pereira 10, Providencia (map) 🗣️ In English ✉️ cdia@inf.udec.cl (logistics) 💻 Lectures + labs
Epoch Tour logo: a loop arrow around the Andes under Chile's lone star

About the workshop

Led by Pavlos Protopapas (Harvard University) and Guillermo Cabrera-Vives (Universidad de Concepción).

Large language models are easy to call and hard to understand. Anyone can wire up an agent in ten lines of code; the hard part is knowing why it works — and why it breaks. This is not a “how to call the API” workshop. It takes practitioners from “I can prompt a model” to “I understand what is happening inside my LLM system, and can design, build and judge one”. It has one through-line: an LLM is not an agent. A model predicts the next token; a useful system wraps that model in retrieval, tools, memory and a control loop — and each layer adds capability, cost and new ways to fail.

Lectures build the mental model: what is going on under the hood, and why. Labs in Google Colab, using the OpenAI Agents SDK, put that model to the test — you change one thing, predict what happens, and see the trade-offs that only appear in code. The goal is to understand, not to copy a recipe. Two industry talks, from CMPC and CDIA (Universidad de Concepción), show how these systems are used in Chile today.

Day 1 · Thu 22

LLMs → RAG

What a language model is, from transformers to ChatGPT, and why prompting alone is not enough. Then retrieval-augmented generation, from naïve RAG to self-correcting variants.

Day 2 · Fri 23

Agents

Reasoning models, the agent loop, tools and MCP; then context engineering, harnesses and skills. Labs: the Cheese Quiz agent and a Travel Planner.

Day 3 · Sat 24

Landscape, multi-agent, limits

Which model and which surface for which job, when more than one agent helps, and the limitations, risks and evaluation of LLM systems.

By the end you will understand — and be able to

  1. Explain what an LLM does — and what it cannot do on its own.
  2. Build a RAG pipeline and choose among retrieval improvements: hybrid search, re-ranking, Self-RAG, Corrective RAG.
  3. Build tool-using agents with the OpenAI Agents SDK, and explain the agent loop, tools and MCP.
  4. Compose agents into orchestrator/worker systems, and recognise when a single agent is enough.
  5. Identify hallucination, sycophancy, bias and prompt-injection risks, and design an evaluation for your own system.

Who it is for

Engineers, ML engineers, data scientists and technical leads who are comfortable in Python and have used an LLM API. No prior experience with agent frameworks is needed.

Schedule

Slides and notebooks are posted here before each session. All times are Santiago time.

Day 1 — LLMs → RAG

TimeSessionMaterials
9:00–9:10
WelcomeWelcome and practicalities
The idea of the workshop, the three days, the team, Wi-Fi and logistics, and the readiness check.
Slides soon
9:10–10:30
LectureLanguage models I — from n-grams to attention
1 What is a language model? Tokenization, n-gram models and their limits. 2 Language models with neural networks: word embeddings and feed-forward models. 3 Attention and transformers (continues after the break).
1 · Language models2 · Neural LMs3 · Attention
10:30–10:50Coffee break
10:50–12:30
LectureLanguage models II — from transformers to ChatGPT
3 Attention and transformers, continued. 4 BERT and GPT: masked and autoregressive models, and how GPT generates text. 5 From GPT to ChatGPT: instruction tuning, reward models and RLHF.
4 · BERT & GPT5 · ChatGPT
12:30–13:30Lunch
13:30–15:10
LabChatGPT lab — from a base model to an assistant
See the morning's ideas in code: GPT-2's next-token probabilities, an instruction-tuned model, temperature and log-probabilities, tokens and cost, why the model has no memory, reasoning models and structured output. Seven short practice exercises. Runs in Colab.
Notebook soon
15:10–15:30Coffee break
15:30–17:00
LectureRetrieval-Augmented Generation
Naïve RAG, better retrieval (hybrid search, re-ranking), Self-RAG and Corrective RAG. Optional: fine-tuning with LoRA/QLoRA.
Slides soon
17:00–17:30
Industry talkIgnacio Becker — CMPC
17:30–18:00
LabRAG lab
Chunk, embed and search eleven books about cheese, then let the LLM answer from them. Runs in Colab — no Docker needed.
Notebook soon

Before you arrive

About 15 minutes. Please do this before Thursday morning.

  1. Bring a laptop with a recent Chrome or Firefox. Everything runs in Google Colab; nothing needs to be installed.
  2. Sign in to a Google account so you can open and save Colab notebooks.
  3. Get an OpenAI API key at platform.openai.com with about USD 10 of credit. The labs use small models; a typical participant spends a few dollars.
  4. Run the readiness check. Open the check notebook in Colab, save a copy to your Drive (File → Save a copy in Drive), add your key under 🔑 Secrets as OPENAI_API_KEY, and run all cells. The last line should print ✅ ready. Every lab works the same way: click Open in Colab, save a copy, run.

Team

Instructors, organizers, teaching and support staff, and guest speakers.

Instructor

Pavlos Protopapas

Harvard University

Instructor

Guillermo Cabrera-Vives

Department of Computer Science, Universidad de Concepción. Leads the Day 3 multi-agent lab.

Teaching team

Mabel Vidal

Department of Computer Science, Universidad de Concepción.

Organizer

Karla Cerda

Executive Director, Centro de Datos e Inteligencia Artificial (CDIA), Universidad de Concepción.

Support team

Valentina Riveros

Workshop support — ask her about logistics.

Teaching assistant

Matías Olivas

Supports the labs.

Guest speaker · Day 1

Ignacio Becker

CMPC

Guest speaker · Day 2

To be announced

Lead ML Engineer, CDIA, Universidad de Concepción

FAQ

Who do I contact about logistics?

For registration, the venue, payments and anything practical, write to the CDIA team at cdia@inf.udec.cl. Questions about the content go to the teaching staff in the room.

Do I need experience with agent frameworks?

No. You should be comfortable in Python and have called an LLM API at least once. We start agents from first principles.

Is the workshop in English or Spanish?

Lectures and materials are in English.

Who pays for the API calls?

You use your own OpenAI API key. The labs are designed to cost a few dollars in total.

Can I keep the materials?

Yes. Slides and notebooks stay on this page after the workshop. Please do not redistribute them without permission.

Something does not work in my notebook.

Run the readiness check first. If it does not print ✅ ready, bring the output to any member of the teaching staff before the first lab.