planning

Decompose the goal into ordered milestones, each composed of atomic commits forming vertical slices. Ground each milestone in cited existing code using exact path:line references, and ship the first draft plan rather than over-iterating.

A plan should contain ordered milestones, dependency mappings, risk assessments, an explicit out-of-scope list, evidence anchors with path:line citations, a prior-art comparison, and an argument trace separating facts from recommendations.

Use planning when a validated nontrivial change needs structure before coding begins. Skip it for trivial changes where the work is already bounded and obvious, since the lifecycle phases are optional, not a mandatory pipeline.

Create an explicit out_of_scope list treated as a hard constraint, not a suggestion. Every downstream milestone inherits this list verbatim, and the planner owns enforcing it throughout execution.

Run a simplifying-insight check before accepting that complexity. Record the null hypothesis, a candidate simpler model, its novel prediction, and the cheapest decisive test to validate the simpler approach.