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Season 5: The AI Proposal · Episode 3 of 8

The Anatomy of a Token

You play: AI Engineering Intern

Included with Core programme and Certification prep
See plans

The situation

A moderation filter for creator comments is behaving erratically: it flags innocent multilingual greetings, fragments streamer emojis into 6 expensive sub-tokens, and fails to count characters. Leo wants to scrap the model, but Amara shows that language models do not read words—they read integer token IDs and attend across context using Q, K, V self-attention.

What you'll learn

  • Subword Byte-Pair Encoding (BPE) and token vocabulary lookup.
  • Embedding matrices and positional coordinate encoding.
  • Scaled dot-product self-attention (Q, K, V matrices).
  • Pre-trained transformer sequence classification heads and token budgeting.

Who you work with

  • Amara Okafor

    ML and Data Engineer

  • Maya Chen

    Senior AI Engineer · Your mentor

  • Jax Rivera

    Creator Partnerships Lead

  • Leo Martins

    Product Manager

  • 8-BIT

    Code Nexus Internal AI Assistant

  • Kabelo Mokoena

    Platform and DevOps Engineer

  • Priya Naidoo

    Cloud Architect

Scenes

  1. 1.The Disappearing Spaces
  2. 2.Tokens Are Not Words
  3. 3.The Geometry of Meaning
  4. 4.The Spotlight of Self-Attention
  5. 5.The Pre-Trained Classifier
  6. 6.Token Economics and Context Budgets
  7. 7.Transformer Architecture Check

What you leave with

You explored the architectural foundation of modern AI: how Byte-Pair Encoding decomposes text into subwords, how embedding matrices provide semantic coordinates, how self-attention routes context dynamically, and how token economics dictate production pricing.

Previous episode

The Model Audition

Next episode

The Caption Heard Around the Office

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