diff --git a/server/src/routes/issues.ts b/server/src/routes/issues.ts
index ad7a8be92cf..ecf1e570d83 100644
--- a/server/src/routes/issues.ts
+++ b/server/src/routes/issues.ts
@@ -113,6 +113,7 @@ import {
   FEEDBACK_DELIVERY_RECOVERY_CAUSE,
   FEEDBACK_DELIVERY_RETRY_WAKE_REASON,
   FEEDBACK_DELIVERY_WAKE_COMMENT_IDS_KEY,
+  hasCompleteFeedbackDispositionCoverage,
   readFeedbackDeliveryRunContext,
 } from "../services/recovery/feedback-delivery.js";
 import { evaluateAgentInvokabilityFromDb } from "../services/agent-invokability.js";
@@ -5019,10 +5020,12 @@ export function issueRoutes(
     }
 
     const handledCommentIds = [...new Set(requested.handledCommentIds)];
-    const deliveredCommentIds = new Set(delivery.commentIds);
-    if (handledCommentIds.some((commentId) => !deliveredCommentIds.has(commentId))) {
+    if (!hasCompleteFeedbackDispositionCoverage({
+      deliveryCommentIds: delivery.commentIds,
+      handledCommentIds,
+    })) {
       res.status(422).json({
-        error: "Feedback disposition comment ids must belong to the current run's feedback batch",
+        error: "Feedback disposition must cover every comment in the current run's feedback batch and no others",
       });
       return { ok: false };
     }
diff --git a/server/src/services/heartbeat.ts b/server/src/services/heartbeat.ts
index 7bb5adb5b02..415ef3a8aad 100644
--- a/server/src/services/heartbeat.ts
+++ b/server/src/services/heartbeat.ts
@@ -238,6 +238,7 @@ import {
   buildFeedbackDeliveryFingerprint,
   buildFeedbackDeliveryRetryIdempotencyKey,
   carriesExplicitFeedbackResume,
+  hasCompleteFeedbackDispositionCoverage,
   isEligibleFeedbackDeliveryWake,
   isSuccessfulFeedbackDeliveryRecoveryMatch,
   readFeedbackDeliveryRetryGeneration,
@@ -10226,9 +10227,10 @@ export function heartbeatService(db: Db, options: HeartbeatServiceOptions = {})
           disposition?.kind !== "feedback_delivery"
           || disposition.rootWakeupRequestId !== delivery.rootWakeupRequestId
         ) return false;
-        const handledIds = new Set(disposition.handledCommentIds);
-        return delivery.commentIds.length > 0
-          && delivery.commentIds.every((commentId) => handledIds.has(commentId));
+        return hasCompleteFeedbackDispositionCoverage({
+          deliveryCommentIds: delivery.commentIds,
+          handledCommentIds: disposition.handledCommentIds,
+        });
       }) ?? null);
     if (!comment) return null;
     const disposition = comment.metadata?.feedbackDisposition;
diff --git a/server/src/services/recovery/feedback-delivery.test.ts b/server/src/services/recovery/feedback-delivery.test.ts
index 2d90b00c431..36d9fdaff28 100644
--- a/server/src/services/recovery/feedback-delivery.test.ts
+++ b/server/src/services/recovery/feedback-delivery.test.ts
@@ -6,6 +6,7 @@ import {
   buildFeedbackDeliveryFingerprint,
   buildFeedbackDeliveryRetryIdempotencyKey,
   decideStrandedFeedbackDeliveryBackstop,
+  hasCompleteFeedbackDispositionCoverage,
   isSuccessfulFeedbackDeliveryRecoveryMatch,
   readFeedbackDeliveryRunContext,
   type StrandedFeedbackDeliveryBackstopProbe,
@@ -168,6 +169,23 @@ describe("successful feedback delivery recovery matching", () => {
   });
 });
 
+describe("feedback disposition coverage", () => {
+  it("requires the handled ids to exactly cover the delivered batch", () => {
+    expect(hasCompleteFeedbackDispositionCoverage({
+      deliveryCommentIds: ["comment-1", "comment-2"],
+      handledCommentIds: ["comment-2", "comment-1"],
+    })).toBe(true);
+    expect(hasCompleteFeedbackDispositionCoverage({
+      deliveryCommentIds: ["comment-1", "comment-2"],
+      handledCommentIds: ["comment-1"],
+    })).toBe(false);
+    expect(hasCompleteFeedbackDispositionCoverage({
+      deliveryCommentIds: ["comment-1"],
+      handledCommentIds: ["comment-1", "comment-2"],
+    })).toBe(false);
+  });
+});
+
 describe("stranded feedback delivery backstop", () => {
   it("requeues exactly one normal-model recovery for the original assignee", () => {
     const decision = decide();
diff --git a/server/src/services/recovery/feedback-delivery.ts b/server/src/services/recovery/feedback-delivery.ts
index 93e0040101b..27a8fdaf1b7 100644
--- a/server/src/services/recovery/feedback-delivery.ts
+++ b/server/src/services/recovery/feedback-delivery.ts
@@ -77,6 +77,21 @@ export function buildFeedbackDeliveryManualRetryIdempotencyKey(input: {
   return `${input.fingerprint}:manual:${input.attempt}`;
 }
 
+export function hasCompleteFeedbackDispositionCoverage(input: {
+  deliveryCommentIds: string[];
+  handledCommentIds: string[];
+}) {
+  const deliveryIds = new Set(
+    input.deliveryCommentIds.map(readNonEmptyString).filter((value): value is string => Boolean(value)),
+  );
+  const handledIds = new Set(
+    input.handledCommentIds.map(readNonEmptyString).filter((value): value is string => Boolean(value)),
+  );
+  return deliveryIds.size > 0
+    && handledIds.size === deliveryIds.size
+    && [...deliveryIds].every((commentId) => handledIds.has(commentId));
+}
+
 export function isSuccessfulFeedbackDeliveryRecoveryMatch(input: {
   handlingEvidence: {
     rootWakeupRequestId: string;
diff --git a/server/src/services/recovery/index.ts b/server/src/services/recovery/index.ts
index 7e9a0173758..fe02abc4568 100644
--- a/server/src/services/recovery/index.ts
+++ b/server/src/services/recovery/index.ts
@@ -41,6 +41,7 @@ export {
   buildFeedbackDeliveryRetryIdempotencyKey,
   carriesExplicitFeedbackResume,
   decideStrandedFeedbackDeliveryBackstop,
+  hasCompleteFeedbackDispositionCoverage,
   isEligibleFeedbackDeliveryWake,
   isSuccessfulFeedbackDeliveryRecoveryMatch,
   readFeedbackDeliveryRetryGeneration,