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Model Primitives

Model Primitives

BasicTopic2 lessons~1h

Lessons, in order

About this topic

The AI base: tokens, context, latency, cost, structured output and the choice between models. Enough to reason about a feature before designing it, and to tell which constraint will bind first.

#LessonThe question it answers
01Tokens and the Context WindowWhat is the budget you are spending, and what happens at the edges?✅
02Cost Per RequestWhat is the arithmetic every AI feature needs and almost none contain?✅
03Latency That Users FeelTime to first token, tokens per second, streaming, and why p95 is the number
04Structured Output and SchemasHow do you get something a program can rely on?
05Tool Calls, and What They Really AreWhat happens when a model asks for something to be run?
06Choosing a ModelFrontier or small, hosted or open weights: what is the real tradeoff?
07Routing, Caching and BatchingWhat are the three cost levers, and what does each cost you in quality?
08The Non Determinism ProblemTemperature, seeds, reproducibility, and what it does to your test suite
09Multimodal InputsWhat changes when the input is an image, a document or audio?
10Rate Limits and CapacityWhat happens at launch when everybody arrives at once?
11Reading a Model CardWhat does a provider tell you, and what do you have to find out yourself?
12What Changes Every Six Months, and What Does NotWhich of your assumptions have an expiry date?

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