---
published: true
id: context-engineering
title: Context Engineering
description: Knowledge captured in João Lopes' learning graph.
tags:
- ai-engineering
- context-window
locale: en
resource: https://joaolopes.dev.br/knowledge/concepts/en/context-engineering/
created: '2026-04-05'
---

# Context Engineering
The practice of designing what a language model sees across an entire session, not just a single message.

## Definition
Context engineering is designing the system that assembles the model's context: which instructions load, which tools are available, what memory persists, which skills are defined, how hooks intercept. Every agentic capability is a context engineering decision. The goal is to make the right outputs probable by shaping the context window before anyone types anything. Prompt engineering is a subset: one message. Context engineering is the whole system.

## Source
- [How Claude Code works](https://code.claude.com/docs/en/how-claude-code-works)
- [Explore the context window](https://code.claude.com/docs/en/context-window)

## Related
- [Prompt Engineering](/concepts/en/prompt-engineering.md)
- [Context Window](/concepts/en/context-window.md)
- [Agentic Capabilities](/concepts/en/agentic-capabilities.md)