diff --git a/lib/shared/thread-utils.js b/lib/shared/thread-utils.js
--- a/lib/shared/thread-utils.js
+++ b/lib/shared/thread-utils.js
@@ -63,7 +63,10 @@
   MinimallyEncodedThreadCurrentUserInfo,
   MinimallyEncodedThreadInfo,
 } from '../types/minimally-encoded-thread-permissions-types.js';
-import { decodeMinimallyEncodedRoleInfo } from '../types/minimally-encoded-thread-permissions-types.js';
+import {
+  decodeMinimallyEncodedRoleInfo,
+  minimallyEncodeThreadInfo,
+} from '../types/minimally-encoded-thread-permissions-types.js';
 import { userRelationshipStatus } from '../types/relationship-types.js';
 import {
   threadPermissionPropagationPrefixes,
@@ -333,7 +336,7 @@
   threadColor,
   name,
   sourceMessageID,
-}: CreatePendingThreadArgs): LegacyThreadInfo {
+}: CreatePendingThreadArgs): MinimallyEncodedThreadInfo {
   const now = Date.now();
   if (!members.some(member => member.id === viewerID)) {
     throw new Error(
@@ -510,7 +513,7 @@
 };
 function baseCreatePendingSidebar(
   input: BaseCreatePendingSidebarInput,
-): LegacyThreadInfo {
+): MinimallyEncodedThreadInfo {
   const {
     sourceMessageInfo,
     parentThreadInfo,
@@ -586,7 +589,7 @@
 };
 function createUnresolvedPendingSidebar(
   input: CreateUnresolvedPendingSidebarInput,
-): LegacyThreadInfo {
+): MinimallyEncodedThreadInfo {
   const {
     sourceMessageInfo,
     parentThreadInfo,
@@ -619,7 +622,7 @@
 };
 async function createPendingSidebar(
   input: CreatePendingSidebarInput,
-): Promise<LegacyThreadInfo> {
+): Promise<MinimallyEncodedThreadInfo> {
   const {
     sourceMessageInfo,
     parentThreadInfo,
@@ -890,7 +893,7 @@
   rawThreadInfo: LegacyRawThreadInfo,
   viewerID: ?string,
   userInfos: UserInfos,
-): LegacyThreadInfo {
+): MinimallyEncodedThreadInfo {
   let threadInfo: LegacyThreadInfo = {
     id: rawThreadInfo.id,
     type: rawThreadInfo.type,
@@ -931,8 +934,7 @@
   if (pinnedCount) {
     threadInfo = { ...threadInfo, pinnedCount };
   }
-
-  return threadInfo;
+  return minimallyEncodeThreadInfo(threadInfo);
 }
 
 function getCurrentUser(