Glossary

Terms, in one line each

Quick lookups. Linked terms have a full knowledge base page.

Agent
A model running in a loop: think, call a tool, look at the result, repeat until the task is done. Covered in episode 9.
Context window
Everything the model can see for a single request: instructions, conversation, documents, tool results.
Embedding
A list of numbers representing the meaning of a piece of text, used to find similar content. Covered in episode 6.
Eval
A repeatable test of AI output quality, made of test cases plus pass/fail criteria. Covered in episode 12.
Fine-tuning
Extra training on your own data to specialize a model. Usually not the first tool to reach for.
Hallucination
When a model states something false or made-up with confidence. Covered in episode 2.
Inference
Running a trained model on a request. The model does not learn during inference.
Knowledge cutoff
The date the model's training data ends. Newer information must come in through context.
LLM
Large language model: a system trained to predict the next token of text, which in practice lets it write, summarize, reason and code.
MCP
Model Context Protocol: an open standard for connecting models to tools and data sources. Covered in episode 10.
Next-token prediction
How an LLM generates: predict one token, append it, repeat.
Non-determinism
The same input can produce different outputs, so you design for a distribution of results.
Parameters
The billions of internal numbers a model adjusts during training. Often called weights.
Prompt injection
Malicious instructions hidden in content the model reads, trying to hijack its behavior. Covered in episode 20.
RAG
Retrieval-augmented generation: fetching relevant documents and putting them into the context before the model answers. Covered in episode 6.
Stateless
The model keeps no memory between calls. The full conversation is resent each time.
Streaming
Showing tokens as they are generated instead of waiting for the full response.
System prompt
Instructions the product places at the start of the context to set the model's role, rules and style. Covered in episode 4.
Temperature
A setting that controls how much randomness goes into choosing each token. Low is predictable; high is varied.
Token
The chunk of text a model reads and writes, roughly ¾ of an English word. Cost, speed and limits are measured in tokens.
Tool use
Letting the model call functions or APIs you define, so it can take actions and fetch data. Covered in episode 7.
Training
The phase where a model learns by adjusting its parameters on huge amounts of text. Done by the AI lab.