phase-boundary-planner

Define phase boundaries by tying each transition to an observable outcome, decision, or artifact rather than dates or activity completion. Specify exit criteria for the ending phase, entry criteria for the next phase, required evidence, and a go/no-go decision owner for each boundary.

Exit criteria are the testable conditions a phase must meet before it ends, while entry criteria are the prerequisites the next phase needs before starting. They should be specific and non-duplicative so a boundary crossing is verifiable rather than subjective.

Use phase boundary planning when the central question is where phases transition and what gates control the crossing. Use milestone planning when the main task is grouping work into outcome-based milestones, and use a roadmap builder when you need a full plan from scratch.

Yes, phases can overlap when the overlap rules are explicit. Define what work may start early, the synchronization point between phases, and the blocking conditions that must hold before dependent work proceeds past the boundary gate.

Crossing too early means starting dependent work before prerequisites, decisions, or risk retirements are resolved, which causes rework and blocked teams. The Skill surfaces these risks per boundary along with fallback paths for externally controlled dependencies.