HSDD Phase Plan: Leaf-Parent to Ordered Phases

Take one leaf-parent node and produce an implementation-ready set of phases. Each phase is the atomic unit of HSDD: it drives exactly one OpenSpec cycle and is sized so the AI run plus human review and manual verification fit one Claude Code rolling window (target ~5h).

Core principle: Define contracts and phases before any code. Each phase is independently testable, contract-bounded, and follows FP progression: types -> pure functions -> effects -> composition.

When to Use

• A node spec (hsdd-spec) marked a node leaf-parent.
• You are ready to deep-dive one node before starting OpenSpec.

Do NOT use for decomposing into sub-nodes (hsdd-spec) or OpenSpec artifacts (proposal/design/tasks belong to the OpenSpec cycle, configured by hsdd-config).