Context Engineering with Path-Scoped Rules and Lazy-Loaded Skills
Martin Fowler·high signal
Birgitta Böckeler's Martin Fowler article formalizes context engineering as a system design discipline distinct from prompting: curating exactly what tokens the agent sees at each step using four layers — always-on CLAUDE.md, path-scoped glob rules, on-demand Skills folders, and MCP servers. Path-scoped rules load only when a matching file enters context, keeping irrelevant instructions out entirely. Skills packages (e.g., skills/stripe-integration/) defer large API references until explicitly invoked, preventing context budget waste on unrelated domains.