diff --git a/README.md b/README.md
index 02b1d83..411964b 100644
--- a/README.md
+++ b/README.md
@@ -47,7 +47,7 @@ Ranker's continuation job is narrow:
 
 `POST /api/rank-feedback` accepts a `prioritix-feature-set-v1`-style payload from Scattermind and returns ranked items plus `buildOrder.doFirst / validateNext / defer / park`. It accepts candidate arrays as `features`, `actions`, `nextMoves`, or `candidates` either at the top level or under `featureSet`, and it can consume a nested `conceptMap.nextActions / nextMoves` artifact directly, so Scattermind can hand off Concept Map next actions without renaming them into fake software features. It also returns a `brief` with source, next-48-hour actions, carried-forward assumptions/constraints/non-goals, and `whatWouldChangeRanking` checks, plus a `handoff` object (`rank-feedback-result-v1`) with source provenance, item trace rows, and contract warnings for missing artifact IDs, source sections, original prompt provenance, or evidence on active items. Keep this contract action-first; do not use it as a reason to add generic dashboard, auth, billing, or workspace layers before the bridge has proof.
 
-Candidate items may include optional 1–10 `rankerHints` (`value`, `effort`, `confidence`, `urgency`, `revenue`, `novelty`, `risk`). Ranker blends those explicit Scattermind hints with text heuristics; `effort` is inverted into feasibility. Hints improve the defended order, but `recommendedLane: "defer"` or `"park"` remains a safety rail so dashboard-swamp items do not get promoted by flashy wording. For clean bridge handoff, Scattermind should send `sourceSection` and `evidenceNeeded` on each active next move. Scattermind can also send `targetAudience`, `constraints`, `assumptions`, and `nonGoals` / `avoid` at the top level, in `featureSet`, or inside `conceptMap.context`; Ranker returns that decision context in `input.decisionContext` and `handoff.decisionContext`, and penalizes candidates that conflict with source non-goals (for example saved workspaces/auth/billing before the continuation proof).
+Candidate items may include optional 1–10 `rankerHints` (`value`, `effort`, `confidence`, `urgency`, `revenue`, `novelty`, `risk`). Ranker blends those explicit Scattermind hints with text heuristics; `effort` is inverted into feasibility. Hints improve the defended order, but `recommendedLane: "defer"` or `"park"` remains a safety rail so dashboard-swamp items do not get promoted by flashy wording. For clean bridge handoff, Scattermind should send `sourceSection` and `evidenceNeeded` on each active next move. Scattermind can also send `targetAudience`, `constraints`, `assumptions`, and `nonGoals` / `avoid` at the top level, in `featureSet`, or inside `conceptMap.context`; Ranker returns that decision context in `input.decisionContext` and `handoff.decisionContext`, and penalizes candidates that conflict with source non-goals (for example saved workspaces/auth/billing before the continuation proof). If Scattermind sends duplicate candidate IDs, Ranker keeps the first ID, suffixes later duplicates (`preview-2`), and reports the normalization in `handoff.warnings` / `handoff.itemTrace` so downstream build-order references remain addressable.
 
 Recommended payload shape:
 
diff --git a/scripts/check-rank-feedback.mjs b/scripts/check-rank-feedback.mjs
index 2dc5dda..63b0a7c 100644
--- a/scripts/check-rank-feedback.mjs
+++ b/scripts/check-rank-feedback.mjs
@@ -208,7 +208,34 @@ try {
   assert.deepEqual(nonGoal.handoff.itemTrace.find(item => item.id === 'workspace-autopilot').nonGoalConflicts, workspace.metrics.nonGoalConflicts);
   assert.ok(!nonGoal.buildOrder.doFirst.includes('workspace-autopilot'));
 
-  console.log(JSON.stringify({ ok: true, top: data.ranked[0].id, hintedTop: hinted.ranked[0].id, actionTop: actions.ranked[0].id, nestedConceptTop: nestedConcept.ranked[0].id, nonGoalTop: nonGoal.ranked[0].id, provenance: data.input.provenance, buildOrder: data.buildOrder }, null, 2));
+  const duplicateIdResponse = await fetch(`${base}/api/rank-feedback`, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({
+      sourceName: 'Scattermind',
+      artifactId: 'concept_map_duplicate_ids',
+      originalPrompt: 'I pasted duplicated next-move IDs from a messy Concept Map export.',
+      idea: 'Ranker should keep handoff rows addressable even if Scattermind sends duplicate candidate IDs.',
+      mode: 'mvp',
+      conceptMap: {
+        nextActions: [
+          { id: 'preview', action: 'Manual build-order preview', why: 'Defends the first move without dashboard machinery.', evidence: 'Can one user act on the preview?', suggestedLane: 'do-first' },
+          { id: 'preview', action: 'Copyable preview brief', why: 'Exports the defended order into notes.', evidence: 'Does the copied brief preserve the next action?', suggestedLane: 'validate-next' },
+          { id: 'workspace', action: 'Saved workspace', why: 'Auth dashboard for every idea.', evidence: 'None yet', suggestedLane: 'park' },
+        ],
+      },
+    }),
+  });
+  assert.equal(duplicateIdResponse.status, 200);
+  const duplicateIds = await duplicateIdResponse.json();
+  assert.deepEqual(duplicateIds.ranked.map(item => item.id).sort(), ['preview', 'preview-2', 'workspace']);
+  assert.equal(new Set(duplicateIds.handoff.itemTrace.map(item => item.id)).size, duplicateIds.handoff.itemTrace.length);
+  assert.equal(duplicateIds.handoff.itemTrace.find(item => item.id === 'preview-2').originalId, 'preview');
+  assert.equal(duplicateIds.handoff.itemTrace.find(item => item.id === 'preview-2').idNormalized, true);
+  assert.ok(duplicateIds.handoff.warnings.some(item => /duplicate source id preview normalized to preview-2/.test(item)));
+  assert.ok(Object.values(duplicateIds.buildOrder).flat().includes('preview-2'));
+
+  console.log(JSON.stringify({ ok: true, top: data.ranked[0].id, hintedTop: hinted.ranked[0].id, actionTop: actions.ranked[0].id, nestedConceptTop: nestedConcept.ranked[0].id, nonGoalTop: nonGoal.ranked[0].id, duplicateIds: duplicateIds.ranked.map(item => item.id), provenance: data.input.provenance, buildOrder: data.buildOrder }, null, 2));
 } finally {
   server.kill('SIGTERM');
 }
diff --git a/server.js b/server.js
index 541453f..77f3bdb 100644
--- a/server.js
+++ b/server.js
@@ -477,6 +477,25 @@ function normalizeFeatureOption(item, index, fallbackId = 'feature', defaultSour
   };
 }
 
+function normalizeOptionIds(options = []) {
+  const seen = new Map();
+  return options.map((option, index) => {
+    const baseId = cleanText(option.id || `option-${index + 1}`, 80) || `option-${index + 1}`;
+    const count = seen.get(baseId) || 0;
+    seen.set(baseId, count + 1);
+    if (count === 0) return { ...option, id: baseId };
+    return {
+      ...option,
+      id: cleanText(`${baseId}-${count + 1}`, 80),
+      provenance: {
+        ...(option.provenance || {}),
+        originalId: baseId,
+        idNormalized: true,
+      },
+    };
+  });
+}
+
 function candidateArrayFrom(...entries) {
   return entries.find(entry => Array.isArray(entry?.items)) || null;
 }
@@ -500,12 +519,12 @@ function optionsFromBody(body = {}) {
   );
   if (rawCandidates) {
     const fallbackId = rawCandidates.sourceSection.toLowerCase().includes('action') ? 'action' : 'feature';
-    return rawCandidates.items.slice(0, 24).map((item, index) => normalizeFeatureOption(item, index, fallbackId, rawCandidates.sourceSection)).filter(item => item.title);
+    return normalizeOptionIds(rawCandidates.items.slice(0, 24).map((item, index) => normalizeFeatureOption(item, index, fallbackId, rawCandidates.sourceSection)).filter(item => item.title));
   }
   if (Array.isArray(body.options)) {
-    return body.options.slice(0, 24).map((item, index) => normalizeFeatureOption(item, index, 'option', 'options')).filter(item => item.title);
+    return normalizeOptionIds(body.options.slice(0, 24).map((item, index) => normalizeFeatureOption(item, index, 'option', 'options')).filter(item => item.title));
   }
-  return parseOptionsFromText(body.optionsText || featureSet.optionsText || conceptMap.optionsText || '');
+  return normalizeOptionIds(parseOptionsFromText(body.optionsText || featureSet.optionsText || conceptMap.optionsText || ''));
 }
 
 function scoreOption(option, mode, context = '', decisionContext = {}) {
@@ -664,6 +683,7 @@ function createHandoffContract({ ranked, provenance, decisionContext }) {
 
   const itemTrace = ranked.map(item => {
     if (!item.provenance?.sourceSection) warnings.push(`missing source section for ${item.id}`);
+    if (item.provenance?.idNormalized) warnings.push(`duplicate source id ${item.provenance.originalId} normalized to ${item.id}`);
     if (!item.factors?.evidenceNeeded && ['do', 'test'].includes(item.lane?.id)) warnings.push(`missing evidence needed for active item ${item.id}`);
     if (item.metrics?.nonGoalConflicts?.length && ['do', 'test'].includes(item.lane?.id)) warnings.push(`active item ${item.id} conflicts with source non-goals: ${item.metrics.nonGoalConflicts.join('; ')}`);
     return {
@@ -672,6 +692,8 @@ function createHandoffContract({ ranked, provenance, decisionContext }) {
       lane: item.lane?.id || 'defer',
       sourceSection: item.provenance?.sourceSection || '',
       sourceId: item.provenance?.sourceId || '',
+      originalId: item.provenance?.originalId || '',
+      idNormalized: Boolean(item.provenance?.idNormalized),
       evidenceNeeded: item.factors?.evidenceNeeded || '',
       nonGoalConflicts: item.metrics?.nonGoalConflicts || [],
     };