The New Rules of Context Engineering for Claude 5

Anthropic's Claude 5, with its 1M-token context window, requires a new discipline of context engineering, as capacity does not equal attention, according to a Medium article by an unnamed author. The piece outlines a decision framework for using RAG, memory, compaction, context editing, and subagents to manage what the model forgets, emphasizing that compaction is a handoff, not a trash can, and that context should be a measured product surface.

Member-only story The New Rules of Context Engineering for Claude 5 A 1M-token window isn’t a 1M-token attention span. Here is the decision framework for RAG, memory, compaction, context editing, and subagents. A 1M-token context window does not give your agent a 1M-token attention span. It gives your system a massive, expensive attic to hide stale tool output, obsolete decisions, and silent performance degradation until production reliability collapses. The real Claude 5 advantage is not more context — it is an operating system for deciding what the agent should forget. If you are using free version of Medium, Please consider use link to access this article for free. , share this article with your friends to support my work. Thank you. following and subscribing In this Article you’ll learn · The 1M-Token Trap: Capacity Is Not Attention 7228 · The Context Routing Map: Five Jobs, Five Primitives 294c · Start With the Bottleneck, Not the Feature 9db2 · Compaction Is a Handoff, Not a Trash Can da38 · Forget Selectively: Editing and Memory Need Governance 02bd · Subagents Earn Their Keep Only When Work Is Truly Separate 43c1 · Make Context a Measured Product Surface 3427 · Conclusion 319d