Context engineering is the discipline of programmatically assembling everything an AI model sees per request, instructions, retrieved knowledge, tool definition
The discipline of programmatically assembling everything an AI model sees per request, instructions, retrieved knowledge, tool definitions, memory, and conversation history, within token budgets, so model behavior is reliable by construction.
By 2026 it has largely superseded wording-focused prompt engineering as the highest-leverage skill in applied AI, because most quality problems trace to what was, or was not, in context rather than to the model. Its core method is ablation testing.