Day 4 | Rewrite Your AGENTS.md and Add Your First Interception Hook
Previous article: Day 3 | Harness Hard Constraints: Static Contracts and Lifecycle Hooks. Now that we understand the principles of static contracts and Hooks, this practice session will have us apply these concepts to transform a real project. This is the L3 practice article. Navigation for subsequent articles: Day Type Topic Day 5 Backbone Tools as Interfaces: Three Extension Paths Day 6 Practice Add a new tool to your Agent Day 7 Backbone Meta-Architecture: Everything is a Plugin Day 8 Backbone Memory, Traces, and Observability Day 9 Practice Graduation project: Build a team-level CI/CD automation Harness Day 10 Phase summary L3 graduation assessment + Harness future trends Have You Encountered This? On Day 3, we broke down the two-layer hard constraint mechanism of Harness: static contracts (AGENTS.md defines permission boundaries) and Hook interception (runtime inspection of every tool call). You know what an AGENTS.md looks like and why permission popups are performative security. The concepts are clear, but the moment you apply them to your own project, problems surface. ...