Update articles/codex_exec_plans.md

Author: friel-openai

articles/codex_exec_plans.md

@@ -174,6 +174,4 @@ In crates/foo/planner.rs, define:
 If you follow the guidance above, a single, stateless agent -- or a human novice -- can read your ExecPlan from top to bottom and produce a working, observable result. That is the bar: SELF-CONTAINED, SELF-SUFFICIENT, NOVICE-GUIDING, OUTCOME-FOCUSED.
 
 When you revise a plan, you must ensure your changes are comprehensively reflected across all sections, including the living document sections, and you must write a note at the bottom of the plan describing the change and the reason why. ExecPlans must describe not just the what but the why for almost everything.
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