blender-syntax-modifiers

Quick Reference

Critical Warnings

NEVER apply modifiers while the object is in Edit Mode — modifier_apply requires Object Mode. Switch with bpy.ops.object.mode_set(mode='OBJECT') first.

NEVER use dict context overrides for modifier_apply in Blender 4.0+ — use context.temp_override() instead. Dict overrides raise TypeError.

NEVER read obj.data.vertices expecting post-modifier results — use obj.evaluated_get(depsgraph).to_mesh() to access evaluated mesh data.

NEVER forget obj_eval.to_mesh_clear() after obj_eval.to_mesh() — this causes memory leaks. ALWAYS use a try/finally block.

NEVER assume Geometry Nodes modifier input identifiers match socket names — identifiers are auto-generated as Socket_N. ALWAYS look up identifiers via modifier.node_group.interface.items_tree.

NEVER modify the evaluated mesh — it is read-only. Modify the original object, then let the depsgraph re-evaluate.

Modifier Type Decision Tree