diff --git a/__tests__/lib/idea-schemas.test.ts b/__tests__/lib/idea-schemas.test.ts
index 1514f5d..637ce1c 100644
--- a/__tests__/lib/idea-schemas.test.ts
+++ b/__tests__/lib/idea-schemas.test.ts
@@ -128,4 +128,21 @@ describe('ideaPlanMdFrontmatterSchema', () => {
     })
     expect(r.success).toBe(false)
   })
+
+  it('accepts plan with task.priority omitted (inherits story-priority via materialize)', () => {
+    const r = ideaPlanMdFrontmatterSchema.safeParse({
+      ...validPlan,
+      stories: [
+        {
+          title: 'Story zonder task-priorities',
+          priority: 2,
+          tasks: [
+            { title: 'Taak 1' }, // geen priority — moet geaccepteerd
+            { title: 'Taak 2', verify_required: 'ALIGNED' },
+          ],
+        },
+      ],
+    })
+    expect(r.success).toBe(true)
+  })
 })
diff --git a/actions/ideas.ts b/actions/ideas.ts
index 94dfc4d..0a2ad09 100644
--- a/actions/ideas.ts
+++ b/actions/ideas.ts
@@ -738,7 +738,11 @@ export async function materializeIdeaPlanAction(
               title: t.title,
               description: t.description ?? null,
               implementation_plan: t.implementation_plan ?? null,
-              priority: t.priority,
+              // Erf priority van de story zodat YAML-volgorde gerespecteerd
+              // blijft. Worker sorteert op `priority ASC, sort_order ASC`;
+              // gemixte task-priorities binnen één story zouden anders de
+              // YAML-volgorde verstoren (zie plan-fix task-volgorde-na-upload).
+              priority: s.priority,
               sort_order: ti + 1,
               status: 'TO_DO',
               verify_required: t.verify_required ?? 'ALIGNED_OR_PARTIAL',
diff --git a/lib/idea-prompts/make-plan.md b/lib/idea-prompts/make-plan.md
index 86891a0..a45500b 100644
--- a/lib/idea-prompts/make-plan.md
+++ b/lib/idea-prompts/make-plan.md
@@ -101,7 +101,8 @@ stories:
           1. Bestand X aanpassen — concrete steps
           2. Test toevoegen Y
           3. Verifieer Z
-        priority: 2
+        # task.priority is optioneel en wordt door materialize GENEGEERD.
+        # Tasks erven story.priority; sort_order = positie in deze tasks-array.
         verify_required: ALIGNED_OR_PARTIAL  # ALIGNED | ALIGNED_OR_PARTIAL | ANY
         verify_only: false                    # true voor pure verify-passes
       - title: "Taak B"
@@ -142,7 +143,12 @@ Beschrijf:
 ## Validatie-regels die de parser afdwingt
 
 - `pbi.title`: 1–200 chars, **verplicht**.
-- `pbi.priority`, `story.priority`, `task.priority`: integer 1–4.
+- `pbi.priority`, `story.priority`: integer 1–4, **verplicht**.
+- `task.priority`: integer 1–4, **optioneel**. **Wordt door materialize genegeerd**
+  ten faveure van story-priority — alle tasks binnen een story erven dezelfde
+  priority. Reden: worker sorteert op `priority ASC, sort_order ASC`; gemixte
+  task-priorities zouden de YAML-volgorde verstoren. De YAML-volgorde *is* de
+  execution-volgorde — daar is `sort_order` (positie in de array) voor.
 - Minimaal 1 story; per story minimaal 1 taak.
 - `implementation_plan`: max 8000 chars.
 - `verify_required`: enum exact `ALIGNED` | `ALIGNED_OR_PARTIAL` | `ANY`.
diff --git a/lib/schemas/idea.ts b/lib/schemas/idea.ts
index 4be1553..a8a32f2 100644
--- a/lib/schemas/idea.ts
+++ b/lib/schemas/idea.ts
@@ -20,11 +20,16 @@ export type IdeaUpdateInput = z.infer<typeof ideaUpdateSchema>
 
 const verifyRequiredEnum = z.enum(['ALIGNED', 'ALIGNED_OR_PARTIAL', 'ANY'])
 
+// Task-level priority is geaccepteerd in het schema voor backward-compat,
+// maar wordt door `materializeIdeaPlanAction` genegeerd ten faveure van
+// story-priority. Reden: worker sorteert op `priority ASC, sort_order ASC`
+// — gemixte task-priorities binnen één story zouden de YAML-volgorde
+// verstoren. Auteurs hoeven het veld dus niet meer in te vullen.
 const planTaskSchema = z.object({
   title: z.string().min(1).max(200),
   description: z.string().max(4000).optional(),
   implementation_plan: z.string().max(8000).optional(),
-  priority: z.number().int().min(1).max(4),
+  priority: z.number().int().min(1).max(4).optional(),
   verify_required: verifyRequiredEnum.optional(),
   verify_only: z.boolean().optional(),
 })