diff --git a/js/algorithm.js b/js/algorithm.js
index 63fe059..0e3458a 100644
--- a/js/algorithm.js
+++ b/js/algorithm.js
@@ -76,9 +76,10 @@ function scoreCandidate(employee, isoDate, allHistory, randomFn) {
   return score;
 }
 
-// Returns [{ date, employeeId, manual: false }] for each assigned workday
+// Returns { assignments: [{ date, employeeId, manual: false }], skippedDates: [] }
 export function generatePlan(workdays, employees, history, randomFn = Math.random) {
   const monthAssignments = [];
+  const skippedDates = [];
 
   for (const date of workdays) {
     const candidates = employees.filter(e =>
@@ -93,5 +94,5 @@ export function generatePlan(workdays, employees, history, randomFn = Math.rando
     monthAssignments.push({ date, employeeId: scored[0].employee.id, manual: false });
   }
 
-  return monthAssignments;
+  return { assignments: monthAssignments, skippedDates };
 }
diff --git a/js/calendar.js b/js/calendar.js
index 94c5013..8aa784e 100644
--- a/js/calendar.js
+++ b/js/calendar.js
@@ -98,7 +98,8 @@ export function renderCalendar() {
       state.calendar.holidays, state.calendar.companyClosures);
     const prefix = currentYear + '-' + String(currentMonth).padStart(2,'0');
     const historyWithoutMonth = state.history.filter(h => !h.date.startsWith(prefix));
-    currentPlan = generatePlan(workdays, state.employees, historyWithoutMonth);
+    const result = generatePlan(workdays, state.employees, historyWithoutMonth);
+    currentPlan = result.assignments;
     addHistoryEntries(state, currentPlan);
     saveState();
     renderGrid(wrapper, exportBtn);
diff --git a/tests/algorithm.test.mjs b/tests/algorithm.test.mjs
index 8e07b79..f0203c8 100644
--- a/tests/algorithm.test.mjs
+++ b/tests/algorithm.test.mjs
@@ -35,15 +35,15 @@ function emp(id, constraints = {}) {
 // generatePlan — basic assignment
 {
   const result = generatePlan(['2026-04-01'], [emp('alice'), emp('bob')], [], fixed);
-  assert.equal(result.length, 1, 'One workday → one assignment');
-  assert.ok(['alice','bob'].includes(result[0].employeeId), 'Assigned to alice or bob');
+  assert.equal(result.assignments.length, 1, 'One workday → one assignment');
+  assert.ok(['alice','bob'].includes(result.assignments[0].employeeId), 'Assigned to alice or bob');
 }
 
 // neverDays blocks employee
 {
   // 2026-04-01 is Wednesday (3)
   const result = generatePlan(['2026-04-01'], [emp('alice', {neverDays:[3]}), emp('bob')], [], fixed);
-  assert.equal(result[0].employeeId, 'bob', 'alice blocked on Wednesday → bob assigned');
+  assert.equal(result.assignments[0].employeeId, 'bob', 'alice blocked on Wednesday → bob assigned');
 }
 
 // onlyDays restricts to specific days
@@ -51,7 +51,7 @@ function emp(id, constraints = {}) {
   // 2026-04-01 = Wednesday (3), 2026-04-02 = Thursday (4)
   const employees = [emp('alice', {onlyDays:[3]}), emp('bob')];
   const result = generatePlan(['2026-04-01','2026-04-02'], employees, [], fixed);
-  const aliceOnThursday = result.find(r => r.date === '2026-04-02' && r.employeeId === 'alice');
+  const aliceOnThursday = result.assignments.find(r => r.date === '2026-04-02' && r.employeeId === 'alice');
   assert.ok(!aliceOnThursday, 'alice with onlyDays:[3] not assigned on Thursday');
 }
 
@@ -62,7 +62,7 @@ function emp(id, constraints = {}) {
     emp('bob')
   ];
   const result = generatePlan(['2026-04-01'], employees, [], fixed);
-  assert.equal(result[0].employeeId, 'bob', 'alice on vacation → bob assigned');
+  assert.equal(result.assignments[0].employeeId, 'bob', 'alice on vacation → bob assigned');
 }
 
 // maxPerMonth cap
@@ -70,7 +70,7 @@ function emp(id, constraints = {}) {
   const days = ['2026-04-01','2026-04-02','2026-04-03'];
   const employees = [emp('alice', {maxPerMonth:1}), emp('bob'), emp('clara')];
   const result = generatePlan(days, employees, [], fixed);
-  const aliceCount = result.filter(r => r.employeeId === 'alice').length;
+  const aliceCount = result.assignments.filter(r => r.employeeId === 'alice').length;
   assert.ok(aliceCount <= 1, 'alice maxPerMonth=1 → assigned at most once');
 }
 
@@ -80,14 +80,14 @@ function emp(id, constraints = {}) {
   const history = [{date:'2026-04-02', employeeId:'alice', manual:false}];
   const employees = [emp('alice', {minGapDays:5}), emp('bob')];
   const result = generatePlan(['2026-04-06'], employees, history, fixed);
-  assert.equal(result[0].employeeId, 'bob', 'alice within minGap (4<5) → bob assigned');
+  assert.equal(result.assignments[0].employeeId, 'bob', 'alice within minGap (4<5) → bob assigned');
 }
 
 // No candidates → day skipped
 {
   // 2026-04-01 = Wednesday (3), only employee blocked
   const result = generatePlan(['2026-04-01'], [emp('alice', {neverDays:[3]})], [], fixed);
-  assert.equal(result.length, 0, 'No candidate → day skipped');
+  assert.equal(result.assignments.length, 0, 'No candidate → day skipped');
 }
 
 // Fairness: less history = higher priority
@@ -96,7 +96,7 @@ function emp(id, constraints = {}) {
     date: '2026-04-0' + i, employeeId: 'alice', manual: false
   }));
   const result = generatePlan(['2026-05-04'], [emp('alice'), emp('bob')], history, fixed);
-  assert.equal(result[0].employeeId, 'bob', 'bob (0 history) beats alice (5 history)');
+  assert.equal(result.assignments[0].employeeId, 'bob', 'bob (0 history) beats alice (5 history)');
 }
 
 // companyClosures excluded from workdays
@@ -112,13 +112,13 @@ function emp(id, constraints = {}) {
   // Both have same history (0) — alice's score gets -5 penalty, bob wins
   const employees = [emp('alice', {lowPriorityDays:[3]}), emp('bob')];
   const result = generatePlan(['2026-04-01'], employees, [], fixed);
-  assert.equal(result[0].employeeId, 'bob', 'alice low priority on Wednesday → bob wins');
+  assert.equal(result.assignments[0].employeeId, 'bob', 'alice low priority on Wednesday → bob wins');
 }
 
 // manual: false on auto-assigned entries
 {
   const result = generatePlan(['2026-04-01'], [emp('alice')], [], fixed);
-  assert.equal(result[0].manual, false, 'auto-assignment sets manual: false');
+  assert.equal(result.assignments[0].manual, false, 'auto-assignment sets manual: false');
 }
 
 console.log('All algorithm tests passed.');