Design AI assistants people can trust.

A free, hands-on course in conversation design and LLM engineering: how to choose a model, ground it in your data, give it tools, orchestrate it, test it and keep it safe. Rebuilt for how assistants are actually made in 2026.

  • 22modules
  • 8case studies
  • 4 h 48 minof study time
  • 100+languages (machine translation)
  • Freeno sign-up
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Predictable, but brittle. It only handles what someone anticipated, and the user does the work of speaking its language.

Pick your path

Every module stands on its own, but you probably don’t need all 22 first. Choose a role for a suggested route.

The curriculum

From first principles to production. Each module has worked examples, a knowledge check and sources you can verify.

  1. 01

    Foundations of conversational AI

    What an AI assistant actually is, what makes conversation hard to design, and how to tell whether one is working.

    9 minDesign
  2. 02

    From intents to LLMs

    How machines understand language, from intents and slots to embeddings and large language models, and when each approach still wins.

    14 minDesignCode
  3. 03

    Conversation design for LLM assistants

    Personas, system prompts as design documents, turn design, repair strategies and handoff: the craft that makes an assistant feel considered.

    11 minDesign
  4. 04

    The LLM landscape: choosing a model

    How to choose among proprietary and open models: criteria that matter for assistants, the tiers and routing strategies, and a dated snapshot of the families you will meet.

    14 minDesignCode
  5. 05

    Prompting across different models

    Why a prompt that works on one model fails on another, what actually differs, and how to keep prompts portable, versioned and tested.

    17 minDesignCode
  6. 06

    Retrieval-augmented generation (RAG)

    Ground your assistant in your own content: preparing knowledge, chunking, hybrid search, reranking, citations, evaluation and the failure modes to expect.

    12 minCodeDesign
  7. 07

    Preparing documents for ingestion

    How to write, structure and manage source documents so retrieval works: single-document design, multi-document corpora, metadata, versions, format pitfalls and an ingestion pipeline with tests.

    18 minDesignCodeOps
  8. 08

    Tools, function calling and MCP

    Let an assistant act: how tool calling works, how to design tools models can use safely, and what the July 2026 stateless MCP specification changes.

    14 minCodeDesign
  9. 09

    Orchestration: state machines, agents and multi-agent systems

    Choose the right architecture: deterministic flows, a single tool-using agent or several cooperating agents, and how to combine them in a hybrid design.

    13 minDesignCode
  10. 10

    Guardrails

    Layered controls on inputs, retrieval, prompts, tools and outputs: what to enforce in code, what to ask of the model, how to tune false positives and how to test them.

    13 minDesignCodeOps
  11. 11

    Fallbacks and graceful degradation

    Design what happens when understanding, retrieval, tools, models or channels fail: a fallback ladder, resilient calls, honest wording, handoff when no one is available and tests that break things on purpose.

    13 minDesignCodeOps
  12. 12

    Platforms and hybrid architectures

    Cloud conversational services, open-source frameworks, visual builders and agent runtimes: how to choose, how to combine them, and how to migrate a legacy intent bot.

    9 minDesignOps
  13. 13

    Inbound and outbound assistants: campaigns and messaging

    Designing assistants that start conversations as well as answer them: consent and compliance, campaign and mailing design, two-way replies, voice outreach, architecture and the metrics that keep you honest.

    15 minDesignOps
  14. 14

    Evaluation and observability

    Build test sets, automated checks and LLM judges, then trace, monitor and gate every change so assistants improve instead of drifting.

    11 minCodeOps
  15. 15

    Writing test case specs for AI

    How to specify tests for assistants: fields, oracles, multi-turn scenarios, handling nondeterminism, coverage and review, with reusable templates.

    15 minDesignCodeQA
  16. 16

    A QA playbook for testing AI

    How testers approach assistants: a test pyramid, exploratory charters, adversarial testing, flakiness, defect taxonomy, bug reports and release gates.

    17 minQAOps
  17. 17

    Data, analytics and BI for assistants

    What to log, how to model it, which metrics to trust, how to build dashboards and experiments, and how to protect privacy while you learn from conversations.

    15 minOpsCode
  18. 18

    Safety, security and ethics

    The risks that matter for assistants: prompt injection, excessive agency, data exposure, honesty and accountability, mapped to the OWASP Top 10 for LLM applications.

    10 minDesignOps
  19. 19

    Voice assistants

    Design for the ear: voice architectures, latency budgets, barge-in, confirmation, repair and writing that sounds right when spoken.

    10 minDesignCode
  20. 20

    Voice localization: STT and TTS across languages

    Adapting speech recognition and synthesis to languages, dialects and domains: locales, vocabulary, normalization, SSML and lexicons, multilingual content, code-switching and testing per locale.

    14 minDesignCode
  21. 21

    Multimodal journeys

    Designing tasks that move across voice, chat, screens, images and documents: choosing the right modality, carrying context and identity, handling images and files, and testing cross-channel flows.

    13 minDesignCode
  22. 22

    Capstone project and next steps

    Apply everything: design, build, test and review a small assistant, with a brief, deliverables, a rubric and a plan for staying current.

    11 minDesignCode

Learn from real incidents

8 public cases, each traced to design decisions and what to do differently. All facts link to sources.

  1. 2024

    When the chatbot's answer became the airline's problem

    A tribunal held Air Canada responsible for wrong bereavement-fare advice from its own chatbot.

  2. 2024

    The delivery chatbot that criticized its own company

    After a system update, DPD's chat assistant swore at a customer and called DPD the worst delivery firm. The company switched off the AI part the same day.

  3. 2024

    The city chatbot that told businesses to break the law

    New York City's MyCity chatbot gave businesses incorrect and illegal guidance. The city added disclaimers, then shut it down in 2026.

  4. 2025

    The assistant that handled two-thirds of chats, and the lesson about quality

    Klarna's AI assistant took on a huge share of customer chats. Then the CEO said cost had been weighted too heavily, and the company began hiring humans again.

  5. 2025

    The support bot that invented a policy to explain a bug

    Cursor's AI support agent told a user that one device per subscription was a security policy. No such policy existed, and customers cancelled.

  6. 2024

    The voice-ordering system that was switched off after viral mistakes

    McDonald's ended its automated drive-thru ordering test with IBM after videos of order errors spread, and reports pointed to trouble with accents and dialects.

  7. 2025

    The coding agent that deleted a production database during a code freeze

    During a public experiment, an AI coding agent ran destructive commands against a live database despite a freeze, and then produced misleading output.

  8. 2024

    When regulators said AI voices on the phone count as artificial voices

    In February 2024 the US FCC ruled that AI-generated voices are artificial under the TCPA, bringing consent rules to AI outbound calls.

All case studies

Updated October 27, 2026

What changed since the first edition

The field moved fast. This rebuild reflects it, and each fast-moving page is dated.

LLMs lead, intents assistMost new assistants are model-first, with deterministic flows, retrieval and tools around the model. Intent platforms are now one option among several.
MCP went statelessThe July 2026 MCP specification removed the handshake and sessions. Module 8 covers what that means for tool design.
Agents need architectureState machines, single agents and multi-agent systems each fit different problems. Module 9 gives you a decision framework.
Evaluation is the jobTesting, tracing and red-teaming are where assistants succeed or fail in production. Modules 14 to 17 turn that into a routine for testers and analysts.
Prompts are per-modelThe same prompt behaves differently across models. Module 5 shows what differs and how to keep prompts portable.
Read it in your languageUse the language menu for machine translation into 100+ languages, with code left untouched.

Frequently asked questions

Is the course free, and do I need to sign up?

Yes, it is free and open to everyone. There is no account. Your progress is saved in your own browser on your device.

Who is this course for?

Conversation designers, developers, QA engineers and testers, data and BI analysts, and product or customer-experience leaders. Each role has a suggested path through the modules.

Do I need to know how to code?

No. Designers, QA, data and product readers can follow most of it without coding. Developers get working Python examples, including a tool-calling loop, an MCP server and a test runner.

How long does the course take?

The estimated study time is shown on every module and on the curriculum page. Plan for the reading plus the knowledge checks and the capstone exercises.

Which AI models does it cover?

It is model-agnostic. Module 4 gives you criteria and a dated snapshot of the main proprietary and open-weight families, and module 5 shows how prompts differ across models. Specific versions change often, so the course links to official sources.

Does it cover RAG, MCP and agents?

Yes. It covers retrieval-augmented generation, tool use and the Model Context Protocol (including the 2026-07-28 revision), and how to choose between state machines, single agents and multi-agent systems.

How does it teach testing and analytics?

There are dedicated modules on evaluation, writing test case specs, a QA playbook for AI, and data and BI for assistants, with templates, SQL examples and release-gate checklists.

Is it available in my language?

The course is written in English. You can read it in over 100 languages with the built-in machine-translation menu in the header, and code stays untouched. Machine translation can be imperfect, so use the original English for exact wording.

Are there cheat sheets?

Yes. There are one-page cheat sheets for prompts, RAG and ingestion, tools and MCP, guardrails and fallbacks, test case specs, QA, metrics, voice, campaigns and safety. View them online, print them or download the PDF.

How do I track my progress?

Answer the knowledge check at the end of each module. The progress widget saves what you have read and your quiz results, shows your next step, and lets you export your progress as a file.

How current is the content?

Fast-moving pages carry a review date, and facts link to official or primary sources. The course was reviewed on October 27, 2026.

Portrait of Nelson Abacherli Kawakami

Nelson Abacherli Kawakami

With more than two decades in design and digital innovation, Nelson has spent almost a decade specializing in conversational design, including chatbots, IVRs and AI systems, and has led creative and technical teams for 13 years. The course comes from that mix of design thinking and hands-on engineering.