- Agent
- Software that pursues a goal by taking actions in a loop — calling tools, reading results, deciding the next step — instead of just answering once.The thing you manage like a junior, not a chatbot you interrogate.
- Agenticadj.
- The property of doing rather than saying. An agentic tool acts on your system; a non-agentic one hands you text and wishes you luck.
- Context window
- How much text a model can hold in mind at once — prompt, files, history, all of it. Measured in tokens.Fill it with junk and quality drops. It’s desk space, not memory.
- Token
- The unit a model reads and bills in — roughly ¾ of a word. "Cheap" and "expensive" models are really cheap and expensive per token.
- Prompt
- What you say to the model. "Prompt engineering" is mostly just being specific about what you want and what "done" looks like.
- System prompt
- The standing instructions a model gets before your message — its job description and house rules. You rarely see it; it shapes everything.
- RAGretrieval-augmented generation
- Fetching relevant documents and stuffing them into the prompt so the model answers from your data, not its training.The unglamorous workhorse behind most "chat with your docs" tools.
- Fine-tuning
- Further-training a base model on your own examples so it defaults to your style or task. Powerful, and usually overkill — try prompting and RAG first.
- Hallucination
- When a model states something false with total confidence. Not lying — it has no idea it’s wrong.The reason "trust, then verify" is a workflow, not a slogan.
- Inference
- Running a trained model to get an answer. "Inference cost" is what you pay every time you use it, as opposed to training it once.
- Temperature
- A dial for randomness. Low = predictable and repetitive; high = creative and occasionally unhinged. Pick per task.
- MCPmodel context protocol
- A common plug shape that lets models connect to tools and data without bespoke glue for each one.USB for AI tools: one standard socket, many devices.
- Eval
- A test suite for model behaviour — cases you score to know whether a change made things better or just different.If you can’t eval it, you’re tuning by vibes.
- Guardrails
- The checks around a model that block bad inputs or outputs. The seatbelt, not the engine — no substitute for a human on risky calls.
- Latency
- How long the model takes to answer. Fine for a draft; ruinous for anything a person waits on live. Often the real product constraint.
- Ground truth
- The verified-correct answer you measure against. Without it, every accuracy claim is a guess wearing a percentage.
- Frontier model
- The current most-capable class of models. Moves every few months — exactly why nothing on this page pins its verdict to a version number.
- Distillation
- Training a small, cheap model to mimic a big expensive one. You lose a little quality and a lot of cost — often a great trade.