SERVER-33135 Remove metadata accessors from command reply APIs

Now that OP_COMMAND is dead, all remaining implementations return the same
BSONObj for data and metadata.

55 files changed, 239 insertions, 342 deletions

diff --git a/src/mongo/client/authenticate.cpp b/src/mongo/client/authenticate.cpp
index fe13099bd2a..f86791dd3af 100644
--- a/src/mongo/client/authenticate.cpp
+++ b/src/mongo/client/authenticate.cpp
@@ -169,8 +169,7 @@ void auth(RunCommandHook runCommand,
                      "authentication.";
 
             // We need to mock a successful AuthResponse.
-            return handler(
-                AuthResponse(RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(0))));
+            return handler(AuthResponse(RemoteCommandResponse(BSON("ok" << 1), Milliseconds(0))));
         }
 
         // otherwise, call handler
diff --git a/src/mongo/client/authenticate_test.cpp b/src/mongo/client/authenticate_test.cpp
index a486b37f131..54cad29b9be 100644
--- a/src/mongo/client/authenticate_test.cpp
+++ b/src/mongo/client/authenticate_test.cpp
@@ -103,7 +103,7 @@ public:
     }
 
     void pushResponse(const BSONObj& cmd) {
-        _responses.emplace(cmd, BSONObj(), _millis);
+        _responses.emplace(cmd, _millis);
     }
 
     void pushRequest(StringData dbname, const BSONObj& cmd) {
diff --git a/src/mongo/client/connection_pool.cpp b/src/mongo/client/connection_pool.cpp
index 3050f281c73..c02ab68ed5d 100644
--- a/src/mongo/client/connection_pool.cpp
+++ b/src/mongo/client/connection_pool.cpp
@@ -207,7 +207,6 @@ ConnectionPool::ConnectionList::iterator ConnectionPool::acquireConnection(
                                                              postConnectRequest->metadata));
 
             auto rcr = executor::RemoteCommandResponse(reply->getCommandReply().getOwned(),
-                                                       reply->getMetadata().getOwned(),
                                                        Date_t::now() - start);
 
             uassertStatusOK(_hook->handleReply(target, std::move(rcr)));
diff --git a/src/mongo/client/dbclient_base.cpp b/src/mongo/client/dbclient_base.cpp
index d0ef3e0ea12..5332e631759 100644
--- a/src/mongo/client/dbclient_base.cpp
+++ b/src/mongo/client/dbclient_base.cpp
@@ -168,7 +168,7 @@ rpc::UniqueReply DBClientBase::parseCommandReplyMessage(const std::string& host,
 
     if (_metadataReader) {
         auto opCtx = haveClient() ? cc().getOperationContext() : nullptr;
-        uassertStatusOK(_metadataReader(opCtx, commandReply->getMetadata(), host));
+        uassertStatusOK(_metadataReader(opCtx, commandReply->getCommandReply(), host));
     }
 
     auto status = getStatusFromCommandResult(commandReply->getCommandReply());
@@ -470,11 +470,10 @@ void DBClientBase::_auth(const BSONObj& params) {
                     OpMsgRequest::fromDBAndBody(request.dbname, request.cmdObj, request.metadata));
 
                 BSONObj data = reply->getCommandReply().getOwned();
-                BSONObj metadata = reply->getMetadata().getOwned();
                 Milliseconds millis(Date_t::now() - start);
 
                 // Hand control back to authenticateClient()
-                handler({data, metadata, millis});
+                handler({data, millis});
 
             } catch (...) {
                 handler(exceptionToStatus());
diff --git a/src/mongo/client/dbclient_connection.cpp b/src/mongo/client/dbclient_connection.cpp
index d0940a873e4..1903f5eaa3a 100644
--- a/src/mongo/client/dbclient_connection.cpp
+++ b/src/mongo/client/dbclient_connection.cpp
@@ -153,8 +153,7 @@ executor::RemoteCommandResponse initWireVersion(DBClientConnection* conn,
 
         conn->getCompressorManager().clientFinish(isMasterObj);
 
-        return executor::RemoteCommandResponse{
-            std::move(isMasterObj), result->getMetadata().getOwned(), finish - start};
+        return executor::RemoteCommandResponse{std::move(isMasterObj), finish - start};
 
     } catch (...) {
         return exceptionToStatus();
diff --git a/src/mongo/client/dbclient_cursor.cpp b/src/mongo/client/dbclient_cursor.cpp
index 321d19d0eef..2d6ea826c42 100644
--- a/src/mongo/client/dbclient_cursor.cpp
+++ b/src/mongo/client/dbclient_cursor.cpp
@@ -262,7 +262,7 @@ BSONObj DBClientCursor::commandDataReceived(const Message& reply) {
     auto opCtx = haveClient() ? cc().getOperationContext() : nullptr;
     if (_client->getReplyMetadataReader()) {
         uassertStatusOK(_client->getReplyMetadataReader()(
-            opCtx, commandReply->getMetadata(), _client->getServerAddress()));
+            opCtx, commandReply->getCommandReply(), _client->getServerAddress()));
     }
 
     return commandReply->getCommandReply().getOwned();
diff --git a/src/mongo/client/fetcher.cpp b/src/mongo/client/fetcher.cpp
index 24eecd6d8b7..facd7aef852 100644
--- a/src/mongo/client/fetcher.cpp
+++ b/src/mongo/client/fetcher.cpp
@@ -361,7 +361,7 @@ void Fetcher::_callback(const RemoteCommandCallbackArgs& rcbd, const char* batch
         return;
     }
 
-    batchData.otherFields.metadata = std::move(rcbd.response.metadata);
+    batchData.otherFields.metadata = std::move(rcbd.response.data);
     batchData.elapsedMillis = rcbd.response.elapsedMillis.value_or(Milliseconds{0});
     {
         stdx::lock_guard<stdx::mutex> lk(_mutex);
diff --git a/src/mongo/client/fetcher_test.cpp b/src/mongo/client/fetcher_test.cpp
index 1da6d23f20d..a50b03ab0aa 100644
--- a/src/mongo/client/fetcher_test.cpp
+++ b/src/mongo/client/fetcher_test.cpp
@@ -143,7 +143,7 @@ void FetcherTest::processNetworkResponse(const BSONObj& obj,
                                          ReadyQueueState readyQueueStateAfterProcessing,
                                          FetcherState fetcherStateAfterProcessing) {
     executor::NetworkInterfaceMock::InNetworkGuard guard(getNet());
-    getNet()->scheduleSuccessfulResponse({obj, {}, elapsed});
+    getNet()->scheduleSuccessfulResponse({obj, elapsed});
     finishProcessingNetworkResponse(readyQueueStateAfterProcessing, fetcherStateAfterProcessing);
 }
 
@@ -947,7 +947,7 @@ TEST_F(FetcherTest, UpdateNextActionAfterSecondBatch) {
         ASSERT_EQUALS(cursorId, cursors.front().numberLong());
 
         // Failed killCursors command response should be logged.
-        getNet()->scheduleSuccessfulResponse(noi, {BSON("ok" << false), {}, Milliseconds(0)});
+        getNet()->scheduleSuccessfulResponse(noi, {BSON("ok" << false), Milliseconds(0)});
         getNet()->runReadyNetworkOperations();
     }
 
diff --git a/src/mongo/client/remote_command_retry_scheduler_test.cpp b/src/mongo/client/remote_command_retry_scheduler_test.cpp
index a3c23c6b05d..783ab23d4c0 100644
--- a/src/mongo/client/remote_command_retry_scheduler_test.cpp
+++ b/src/mongo/client/remote_command_retry_scheduler_test.cpp
@@ -378,7 +378,7 @@ TEST_F(RemoteCommandRetrySchedulerTest, SchedulerInvokesCallbackOnFirstSuccessfu
     start(&scheduler);
 
     // Elapsed time in response is ignored on successful responses.
-    ResponseStatus response(BSON("ok" << 1 << "x" << 123), BSON("z" << 456), Milliseconds(100));
+    ResponseStatus response(BSON("ok" << 1 << "x" << 123 << "z" << 456), Milliseconds(100));
 
     processNetworkResponse(response);
     checkCompletionStatus(&scheduler, callback, response);
@@ -400,8 +400,9 @@ TEST_F(RemoteCommandRetrySchedulerTest, SchedulerIgnoresEmbeddedErrorInSuccessfu
     // This is the case with some commands (e.g. find) which do not always return errors using the
     // wire protocol.
     ResponseStatus response(BSON("ok" << 0 << "code" << int(ErrorCodes::FailedToParse) << "errmsg"
-                                      << "injected error"),
-                            BSON("z" << 456),
+                                      << "injected error"
+                                      << "z"
+                                      << 456),
                             Milliseconds(100));
 
     processNetworkResponse(response);
@@ -458,7 +459,7 @@ TEST_F(RemoteCommandRetrySchedulerTest, SchedulerShouldRetryUntilSuccessfulRespo
 
     processNetworkResponse({ErrorCodes::HostNotFound, "first", Milliseconds(0)});
 
-    ResponseStatus response(BSON("ok" << 1 << "x" << 123), BSON("z" << 456), Milliseconds(100));
+    ResponseStatus response(BSON("ok" << 1 << "x" << 123 << "z" << 456), Milliseconds(100));
     processNetworkResponse(response);
     checkCompletionStatus(&scheduler, callback, response);
 }
diff --git a/src/mongo/db/commands.cpp b/src/mongo/db/commands.cpp
index 57e82e49067..63500fe2af4 100644
--- a/src/mongo/db/commands.cpp
+++ b/src/mongo/db/commands.cpp
@@ -519,7 +519,6 @@ void Command::generateHelpResponse(OperationContext* opCtx,
     helpBuilder.append("help",
                        str::stream() << "help for: " << command.getName() << " " << command.help());
     replyBuilder->setCommandReply(helpBuilder.obj());
-    replyBuilder->setMetadata(rpc::makeEmptyMetadata());
 }
 
 bool ErrmsgCommandDeprecated::run(OperationContext* opCtx,
diff --git a/src/mongo/db/repl/abstract_oplog_fetcher_test.cpp b/src/mongo/db/repl/abstract_oplog_fetcher_test.cpp
index 388e1492461..13446ed9ff5 100644
--- a/src/mongo/db/repl/abstract_oplog_fetcher_test.cpp
+++ b/src/mongo/db/repl/abstract_oplog_fetcher_test.cpp
@@ -451,8 +451,7 @@ TEST_F(AbstractOplogFetcherTest, OplogFetcherTimesOutCorrectlyOnInitialFindReque
     net->enterNetwork();
     auto when = net->now() + initialFindMaxTime + kNetworkTimeoutBufferMS + Milliseconds(10);
     auto noi = getNet()->getNextReadyRequest();
-    RemoteCommandResponse response = {
-        {makeCursorResponse(1, {ops[0], ops[1]})}, rpc::makeEmptyMetadata(), Milliseconds(0)};
+    RemoteCommandResponse response = {{makeCursorResponse(1, {ops[0], ops[1]})}, Milliseconds(0)};
     auto request = net->scheduleSuccessfulResponse(noi, when, response);
     net->runUntil(when);
     net->runReadyNetworkOperations();
@@ -492,8 +491,7 @@ TEST_F(AbstractOplogFetcherTest, OplogFetcherTimesOutCorrectlyOnRetriedFindReque
     net->enterNetwork();
     auto when = net->now() + initialFindMaxTime + kNetworkTimeoutBufferMS + Milliseconds(10);
     auto noi = getNet()->getNextReadyRequest();
-    RemoteCommandResponse response = {
-        {makeCursorResponse(1, {ops[0], ops[1]})}, rpc::makeEmptyMetadata(), Milliseconds(0)};
+    RemoteCommandResponse response = {{makeCursorResponse(1, {ops[0], ops[1]})}, Milliseconds(0)};
     auto request = net->scheduleSuccessfulResponse(noi, when, response);
     net->runUntil(when);
     net->runReadyNetworkOperations();
@@ -503,8 +501,7 @@ TEST_F(AbstractOplogFetcherTest, OplogFetcherTimesOutCorrectlyOnRetriedFindReque
     net->enterNetwork();
     when = net->now() + retriedFindMaxTime + kNetworkTimeoutBufferMS + Milliseconds(10);
     noi = getNet()->getNextReadyRequest();
-    response = {
-        {makeCursorResponse(1, {ops[0], ops[1]})}, rpc::makeEmptyMetadata(), Milliseconds(0)};
+    response = {{makeCursorResponse(1, {ops[0], ops[1]})}, Milliseconds(0)};
     request = net->scheduleSuccessfulResponse(noi, when, response);
     net->runUntil(when);
     net->runReadyNetworkOperations();
diff --git a/src/mongo/db/repl/abstract_oplog_fetcher_test_fixture.cpp b/src/mongo/db/repl/abstract_oplog_fetcher_test_fixture.cpp
index 2b0696c8531..ed0e0f9105a 100644
--- a/src/mongo/db/repl/abstract_oplog_fetcher_test_fixture.cpp
+++ b/src/mongo/db/repl/abstract_oplog_fetcher_test_fixture.cpp
@@ -139,8 +139,7 @@ executor::RemoteCommandRequest AbstractOplogFetcherTest::processNetworkResponse(
 
 executor::RemoteCommandRequest AbstractOplogFetcherTest::processNetworkResponse(
     BSONObj obj, bool expectReadyRequestsAfterProcessing) {
-    return processNetworkResponse({obj, rpc::makeEmptyMetadata(), Milliseconds(0)},
-                                  expectReadyRequestsAfterProcessing);
+    return processNetworkResponse({obj, Milliseconds(0)}, expectReadyRequestsAfterProcessing);
 }
 
 }  // namespace repl
diff --git a/src/mongo/db/repl/base_cloner_test_fixture.cpp b/src/mongo/db/repl/base_cloner_test_fixture.cpp
index 8fb69472329..88d0a84d996 100644
--- a/src/mongo/db/repl/base_cloner_test_fixture.cpp
+++ b/src/mongo/db/repl/base_cloner_test_fixture.cpp
@@ -162,7 +162,7 @@ const Status& BaseClonerTest::getStatus() const {
 void BaseClonerTest::scheduleNetworkResponse(NetworkOperationIterator noi, const BSONObj& obj) {
     auto net = getNet();
     Milliseconds millis(0);
-    RemoteCommandResponse response(obj, BSONObj(), millis);
+    RemoteCommandResponse response(obj, millis);
     log() << "Scheduling response to request:" << noi->getDiagnosticString() << " -- resp:" << obj;
     net->scheduleResponse(noi, net->now(), response);
 }
diff --git a/src/mongo/db/repl/check_quorum_for_config_change.cpp b/src/mongo/db/repl/check_quorum_for_config_change.cpp
index 67204eed65c..f5c967163d0 100644
--- a/src/mongo/db/repl/check_quorum_for_config_change.cpp
+++ b/src/mongo/db/repl/check_quorum_for_config_change.cpp
@@ -226,7 +226,7 @@ void QuorumChecker::_tabulateHeartbeatResponse(const RemoteCommandRequest& reque
 
     if (_rsConfig->hasReplicaSetId()) {
         StatusWith<rpc::ReplSetMetadata> replMetadata =
-            rpc::ReplSetMetadata::readFromMetadata(response.metadata);
+            rpc::ReplSetMetadata::readFromMetadata(response.data);
         if (replMetadata.isOK() && replMetadata.getValue().getReplicaSetId().isSet() &&
             _rsConfig->getReplicaSetId() != replMetadata.getValue().getReplicaSetId()) {
             std::string message = str::stream()
diff --git a/src/mongo/db/repl/check_quorum_for_config_change_test.cpp b/src/mongo/db/repl/check_quorum_for_config_change_test.cpp
index 2d4c0416b3e..7829fd72ec5 100644
--- a/src/mongo/db/repl/check_quorum_for_config_change_test.cpp
+++ b/src/mongo/db/repl/check_quorum_for_config_change_test.cpp
@@ -233,7 +233,7 @@ const BSONObj makeHeartbeatRequest(const ReplSetConfig& rsConfig, int myConfigIn
 executor::RemoteCommandResponse makeHeartbeatResponse(const ReplSetConfig& rsConfig,
                                                       const stdx::chrono::milliseconds millis,
                                                       const long long configVersion = 0,
-                                                      const BSONObj& metadata = {}) {
+                                                      const BSONObj& extraFields = {}) {
     ReplSetHeartbeatResponse hbResp;
     hbResp.setSetName(rsConfig.getReplSetName());
     hbResp.setConfigVersion(configVersion);
@@ -241,7 +241,9 @@ executor::RemoteCommandResponse makeHeartbeatResponse(const ReplSetConfig& rsCon
     OpTime opTime(Timestamp(), 0);
     hbResp.setAppliedOpTime(opTime);
     hbResp.setDurableOpTime(opTime);
-    return RemoteCommandResponse(hbResp.toBSON(), metadata, duration_cast<Milliseconds>(millis));
+    auto bob = BSONObjBuilder(hbResp.toBSON());
+    bob.appendElements(extraFields);
+    return RemoteCommandResponse(bob.obj(), duration_cast<Milliseconds>(millis));
 }
 
 TEST_F(CheckQuorumForInitiate, QuorumCheckSuccessForFiveNodes) {
@@ -399,13 +401,10 @@ TEST_F(CheckQuorumForInitiate, QuorumCheckFailedDueToSetNameMismatch) {
                 (RemoteCommandResponse(
                     BSON("ok" << 0 << "code" << ErrorCodes::InconsistentReplicaSetNames << "errmsg"
                               << "replica set name doesn't match."),
-                    BSONObj(),
                     Milliseconds(8))));
         } else {
             getNet()->scheduleResponse(
-                noi,
-                startDate + 10ms,
-                (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(8))));
+                noi, startDate + 10ms, RemoteCommandResponse(BSON("ok" << 1), Milliseconds(8)));
         }
     }
     getNet()->runUntil(startDate + 10ms);
@@ -473,14 +472,14 @@ TEST_F(CheckQuorumForInitiate, QuorumCheckFailedDueToSetIdMismatch) {
                                           unexpectedId,
                                           rpc::ReplSetMetadata::kNoPrimary,
                                           -1);
-            BSONObjBuilder metadataBuilder;
-            metadata.writeToMetadata(&metadataBuilder).transitional_ignore();
+            BSONObjBuilder bob;
+            uassertStatusOK(metadata.writeToMetadata(&bob));
 
             long long configVersion = 0;
             getNet()->scheduleResponse(
                 noi,
                 startDate + 10ms,
-                makeHeartbeatResponse(rsConfig, 8ms, configVersion, metadataBuilder.obj()));
+                makeHeartbeatResponse(rsConfig, 8ms, configVersion, bob.obj()));
         } else {
             getNet()->scheduleResponse(noi, startDate + 10ms, makeHeartbeatResponse(rsConfig, 8ms));
         }
@@ -713,7 +712,6 @@ TEST_F(CheckQuorumForReconfig, QuorumCheckVetoedDueToIncompatibleSetName) {
                 (RemoteCommandResponse(
                     BSON("ok" << 0 << "code" << ErrorCodes::InconsistentReplicaSetNames << "errmsg"
                               << "replica set name doesn't match."),
-                    BSONObj(),
                     Milliseconds(8))));
         } else {
             getNet()->scheduleResponse(
@@ -949,10 +947,9 @@ TEST_F(CheckQuorumForReconfig, QuorumCheckProcessesCallbackCanceledResponse) {
                 startDate + 10ms,
                 (RemoteCommandResponse(ErrorCodes::CallbackCanceled, "Testing canceled callback")));
         } else {
-            getNet()->scheduleResponse(
-                noi,
-                startDate + 10ms,
-                (RemoteCommandResponse(BSON("ok" << 0), BSONObj(), Milliseconds(8))));
+            getNet()->scheduleResponse(noi,
+                                       startDate + Milliseconds(10),
+                                       RemoteCommandResponse(BSON("ok" << 0), Milliseconds(8)));
         }
     }
     getNet()->runUntil(startDate + 10ms);
diff --git a/src/mongo/db/repl/databases_cloner_test.cpp b/src/mongo/db/repl/databases_cloner_test.cpp
index f32c83c756a..66f2138ceaa 100644
--- a/src/mongo/db/repl/databases_cloner_test.cpp
+++ b/src/mongo/db/repl/databases_cloner_test.cpp
@@ -104,7 +104,7 @@ public:
                                  const BSONObj& obj) {
         NetworkInterfaceMock* net = getNet();
         Milliseconds millis(0);
-        RemoteCommandResponse response(obj, BSONObj(), millis);
+        RemoteCommandResponse response(obj, millis);
         net->scheduleResponse(noi, net->now(), response);
     }
 
@@ -242,11 +242,10 @@ protected:
             log() << "Sending response for network request:";
             log() << "     req: " << noi->getRequest().dbname << "." << noi->getRequest().cmdObj;
             log() << "     resp:" << responses[processedRequests].second;
-            net->scheduleResponse(noi,
-                                  net->now(),
-                                  RemoteCommandResponse(responses[processedRequests].second,
-                                                        BSONObj(),
-                                                        Milliseconds(10)));
+            net->scheduleResponse(
+                noi,
+                net->now(),
+                RemoteCommandResponse(responses[processedRequests].second, Milliseconds(10)));
 
             if ((Date_t::now() - lastLog) > Seconds(1)) {
                 lastLog = Date_t();
diff --git a/src/mongo/db/repl/initial_syncer_test.cpp b/src/mongo/db/repl/initial_syncer_test.cpp
index 2948a08ff01..fe3483cb792 100644
--- a/src/mongo/db/repl/initial_syncer_test.cpp
+++ b/src/mongo/db/repl/initial_syncer_test.cpp
@@ -162,7 +162,7 @@ public:
                                  const BSONObj& obj) {
         NetworkInterfaceMock* net = getNet();
         Milliseconds millis(0);
-        RemoteCommandResponse response(obj, BSONObj(), millis);
+        RemoteCommandResponse response(obj, millis);
         log() << "Sending response for network request:";
         log() << "     req: " << noi->getRequest().dbname << "." << noi->getRequest().cmdObj;
         log() << "     resp:" << response;
@@ -501,9 +501,6 @@ RemoteCommandResponse makeCursorResponse(CursorId cursorId,
                                          int rbid = 1) {
     OpTime futureOpTime(Timestamp(1000, 1000), 1000);
     rpc::OplogQueryMetadata oqMetadata(futureOpTime, futureOpTime, rbid, 0, 0);
-    BSONObjBuilder metadataBob;
-    ASSERT_OK(oqMetadata.writeToMetadata(&metadataBob));
-    auto metadataObj = metadataBob.obj();
 
     BSONObjBuilder bob;
     {
@@ -518,8 +515,9 @@ RemoteCommandResponse makeCursorResponse(CursorId cursorId,
             }
         }
     }
+    ASSERT_OK(oqMetadata.writeToMetadata(&bob));
     bob.append("ok", 1);
-    return {bob.obj(), metadataObj, Milliseconds(0)};
+    return {bob.obj(), Milliseconds()};
 }
 
 /**
diff --git a/src/mongo/db/repl/oplog_fetcher_test.cpp b/src/mongo/db/repl/oplog_fetcher_test.cpp
index 5209ea0c4e3..8f03c6c50cb 100644
--- a/src/mongo/db/repl/oplog_fetcher_test.cpp
+++ b/src/mongo/db/repl/oplog_fetcher_test.cpp
@@ -192,8 +192,7 @@ std::unique_ptr<ShutdownState> OplogFetcherTest::processSingleBatch(RemoteComman
 
 std::unique_ptr<ShutdownState> OplogFetcherTest::processSingleBatch(BSONObj obj,
                                                                     bool requireFresherSyncSource) {
-    return processSingleBatch({obj, rpc::makeEmptyMetadata(), Milliseconds(0)},
-                              requireFresherSyncSource);
+    return processSingleBatch({obj, Milliseconds(0)}, requireFresherSyncSource);
 }
 
 void _checkDefaultCommandObjectFields(BSONObj cmdObj) {
@@ -219,6 +218,12 @@ std::unique_ptr<OplogFetcher> OplogFetcherTest::makeOplogFetcher(ReplSetConfig c
                                            defaultBatchSize);
 }
 
+BSONObj concatenate(BSONObj a, const BSONObj& b) {
+    auto bob = BSONObjBuilder(std::move(a));
+    bob.appendElements(b);
+    return bob.obj();
+}
+
 TEST_F(
     OplogFetcherTest,
     FindQueryContainsTermAndStartTimestampIfGetCurrentTermAndLastCommittedOpTimeReturnsValidTerm) {
@@ -255,19 +260,21 @@ TEST_F(OplogFetcherTest, AwaitDataTimeoutShouldEqualHalfElectionTimeoutUnderProt
 }
 
 TEST_F(OplogFetcherTest, InvalidReplSetMetadataInResponseStopsTheOplogFetcher) {
-    auto shutdownState = processSingleBatch(
-        {makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}),
-         BSON(rpc::kReplSetMetadataFieldName << BSON("invalid_repl_metadata_field" << 1)),
-         Milliseconds(0)});
+    auto shutdownState =
+        processSingleBatch({concatenate(makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}),
+                                        BSON(rpc::kReplSetMetadataFieldName
+                                             << BSON("invalid_repl_metadata_field" << 1))),
+                            Milliseconds(0)});
 
     ASSERT_EQUALS(ErrorCodes::NoSuchKey, shutdownState->getStatus());
 }
 
 TEST_F(OplogFetcherTest, InvalidOplogQueryMetadataInResponseStopsTheOplogFetcher) {
-    auto shutdownState = processSingleBatch(
-        {makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}),
-         BSON(rpc::kOplogQueryMetadataFieldName << BSON("invalid_oq_metadata_field" << 1)),
-         Milliseconds(0)});
+    auto shutdownState =
+        processSingleBatch({concatenate(makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}),
+                                        BSON(rpc::kOplogQueryMetadataFieldName
+                                             << BSON("invalid_oq_metadata_field" << 1))),
+                            Milliseconds(0)});
 
     ASSERT_EQUALS(ErrorCodes::NoSuchKey, shutdownState->getStatus());
 }
@@ -279,10 +286,11 @@ TEST_F(OplogFetcherTest,
     ASSERT_OK(metadata.writeToMetadata(&bob));
     auto metadataObj = bob.obj();
 
-    ASSERT_OK(processSingleBatch({makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}),
-                                  metadataObj,
-                                  Milliseconds(0)})
-                  ->getStatus());
+    ASSERT_OK(
+        processSingleBatch(
+            {concatenate(makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}), metadataObj),
+             Milliseconds(0)})
+            ->getStatus());
     ASSERT_TRUE(dataReplicatorExternalState->metadataWasProcessed);
     ASSERT_EQUALS(metadata.getPrimaryIndex(),
                   dataReplicatorExternalState->replMetadataProcessed.getPrimaryIndex());
@@ -296,10 +304,11 @@ TEST_F(OplogFetcherTest, ValidMetadataWithInResponseShouldBeForwardedToProcessMe
     ASSERT_OK(replMetadata.writeToMetadata(&bob));
     ASSERT_OK(oqMetadata.writeToMetadata(&bob));
     auto metadataObj = bob.obj();
-    ASSERT_OK(processSingleBatch({makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}),
-                                  metadataObj,
-                                  Milliseconds(0)})
-                  ->getStatus());
+    ASSERT_OK(
+        processSingleBatch(
+            {concatenate(makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}), metadataObj),
+             Milliseconds(0)})
+            ->getStatus());
     ASSERT_TRUE(dataReplicatorExternalState->metadataWasProcessed);
     ASSERT_EQUALS(replMetadata.getPrimaryIndex(),
                   dataReplicatorExternalState->replMetadataProcessed.getPrimaryIndex());
@@ -315,11 +324,12 @@ TEST_F(OplogFetcherTest, MetadataAndBatchAreNotProcessedWhenSyncSourceRollsBack)
     ASSERT_OK(oqMetadata.writeToMetadata(&bob));
     auto metadataObj = bob.obj();
 
-    ASSERT_EQUALS(ErrorCodes::InvalidSyncSource,
-                  processSingleBatch({makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}),
-                                      metadataObj,
-                                      Milliseconds(0)})
-                      ->getStatus());
+    ASSERT_EQUALS(
+        ErrorCodes::InvalidSyncSource,
+        processSingleBatch(
+            {concatenate(makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}), metadataObj),
+             Milliseconds(0)})
+            ->getStatus());
     ASSERT_FALSE(dataReplicatorExternalState->metadataWasProcessed);
     ASSERT(lastEnqueuedDocuments.empty());
 }
@@ -332,11 +342,12 @@ TEST_F(OplogFetcherTest, MetadataAndBatchAreNotProcessedWhenSyncSourceIsBehind)
     ASSERT_OK(oqMetadata.writeToMetadata(&bob));
     auto metadataObj = bob.obj();
 
-    ASSERT_EQUALS(ErrorCodes::InvalidSyncSource,
-                  processSingleBatch({makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}),
-                                      metadataObj,
-                                      Milliseconds(0)})
-                      ->getStatus());
+    ASSERT_EQUALS(
+        ErrorCodes::InvalidSyncSource,
+        processSingleBatch(
+            {concatenate(makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}), metadataObj),
+             Milliseconds(0)})
+            ->getStatus());
     ASSERT_FALSE(dataReplicatorExternalState->metadataWasProcessed);
     ASSERT(lastEnqueuedDocuments.empty());
 }
@@ -349,11 +360,12 @@ TEST_F(OplogFetcherTest, MetadataAndBatchAreNotProcessedWhenSyncSourceIsNotAhead
     ASSERT_OK(oqMetadata.writeToMetadata(&bob));
     auto metadataObj = bob.obj();
 
-    ASSERT_EQUALS(ErrorCodes::InvalidSyncSource,
-                  processSingleBatch({makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}),
-                                      metadataObj,
-                                      Milliseconds(0)})
-                      ->getStatus());
+    ASSERT_EQUALS(
+        ErrorCodes::InvalidSyncSource,
+        processSingleBatch(
+            {concatenate(makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}), metadataObj),
+             Milliseconds(0)})
+            ->getStatus());
     ASSERT_FALSE(dataReplicatorExternalState->metadataWasProcessed);
     ASSERT(lastEnqueuedDocuments.empty());
 }
@@ -370,7 +382,8 @@ TEST_F(OplogFetcherTest,
     auto entry = makeNoopOplogEntry({123LL, staleOpTime});
     ASSERT_EQUALS(
         ErrorCodes::InvalidSyncSource,
-        processSingleBatch({makeCursorResponse(0, {entry}), metadataObj, Milliseconds(0)}, false)
+        processSingleBatch(
+            {concatenate(makeCursorResponse(0, {entry}), metadataObj), Milliseconds(0)}, false)
             ->getStatus());
     ASSERT_FALSE(dataReplicatorExternalState->metadataWasProcessed);
     ASSERT(lastEnqueuedDocuments.empty());
@@ -388,8 +401,8 @@ TEST_F(OplogFetcherTest, MetadataAndBatchAreProcessedWhenSyncSourceIsCurrentButM
     auto metadataObj = bob.obj();
 
     auto entry = makeNoopOplogEntry(lastFetched);
-    auto shutdownState =
-        processSingleBatch({makeCursorResponse(0, {entry}), metadataObj, Milliseconds(0)}, false);
+    auto shutdownState = processSingleBatch(
+        {concatenate(makeCursorResponse(0, {entry}), metadataObj), Milliseconds(0)}, false);
     ASSERT_OK(shutdownState->getStatus());
     ASSERT(dataReplicatorExternalState->metadataWasProcessed);
 }
@@ -404,8 +417,8 @@ TEST_F(OplogFetcherTest,
     auto metadataObj = bob.obj();
 
     auto entry = makeNoopOplogEntry(lastFetched);
-    auto shutdownState =
-        processSingleBatch({makeCursorResponse(0, {entry}), metadataObj, Milliseconds(0)}, false);
+    auto shutdownState = processSingleBatch(
+        {concatenate(makeCursorResponse(0, {entry}), metadataObj), Milliseconds(0)}, false);
     ASSERT_OK(shutdownState->getStatus());
     ASSERT(dataReplicatorExternalState->metadataWasProcessed);
 }
@@ -418,8 +431,9 @@ TEST_F(OplogFetcherTest,
     auto metadataObj = bob.obj();
     ASSERT_EQUALS(ErrorCodes::OplogStartMissing,
                   processSingleBatch(
-                      {makeCursorResponse(0, {makeNoopOplogEntry(Seconds(456), lastFetched.value)}),
-                       metadataObj,
+                      {concatenate(makeCursorResponse(
+                                       0, {makeNoopOplogEntry(Seconds(456), lastFetched.value)}),
+                                   metadataObj),
                        Milliseconds(0)})
                       ->getStatus());
     ASSERT_FALSE(dataReplicatorExternalState->metadataWasProcessed);
@@ -434,17 +448,17 @@ TEST_F(OplogFetcherTest, MetadataIsNotProcessedOnBatchThatTriggersRollback) {
     auto metadataObj = bob.obj();
     ASSERT_EQUALS(ErrorCodes::OplogStartMissing,
                   processSingleBatch(
-                      {makeCursorResponse(0, {makeNoopOplogEntry(Seconds(456), lastFetched.value)}),
-                       metadataObj,
+                      {concatenate(makeCursorResponse(
+                                       0, {makeNoopOplogEntry(Seconds(456), lastFetched.value)}),
+                                   metadataObj),
                        Milliseconds(0)})
                       ->getStatus());
     ASSERT_FALSE(dataReplicatorExternalState->metadataWasProcessed);
 }
 
 TEST_F(OplogFetcherTest, EmptyMetadataIsNotProcessed) {
-    ASSERT_OK(processSingleBatch({makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}),
-                                  rpc::makeEmptyMetadata(),
-                                  Milliseconds(0)})
+    ASSERT_OK(processSingleBatch(
+                  {makeCursorResponse(0, {makeNoopOplogEntry(lastFetched)}), Milliseconds(0)})
                   ->getStatus());
     ASSERT_FALSE(dataReplicatorExternalState->metadataWasProcessed);
 }
@@ -456,10 +470,10 @@ TEST_F(OplogFetcherTest, EmptyFirstBatchStopsOplogFetcherWithOplogStartMissingEr
 
 TEST_F(OplogFetcherTest, MissingOpTimeInFirstDocumentCausesOplogFetcherToStopWithInvalidBSONError) {
     auto metadataObj = makeOplogQueryMetadataObject(remoteNewerOpTime, rbid, 2, 2);
-    ASSERT_EQUALS(
-        ErrorCodes::InvalidBSON,
-        processSingleBatch({makeCursorResponse(0, {BSONObj()}), metadataObj, Milliseconds(0)})
-            ->getStatus());
+    ASSERT_EQUALS(ErrorCodes::InvalidBSON,
+                  processSingleBatch({concatenate(makeCursorResponse(0, {BSONObj()}), metadataObj),
+                                      Milliseconds(0)})
+                      ->getStatus());
 }
 
 TEST_F(
@@ -468,8 +482,9 @@ TEST_F(
     auto metadataObj = makeOplogQueryMetadataObject(remoteNewerOpTime, rbid, 2, 2);
     ASSERT_EQUALS(ErrorCodes::OplogStartMissing,
                   processSingleBatch(
-                      {makeCursorResponse(0, {makeNoopOplogEntry(Seconds(456), lastFetched.value)}),
-                       metadataObj,
+                      {concatenate(makeCursorResponse(
+                                       0, {makeNoopOplogEntry(Seconds(456), lastFetched.value)}),
+                                   metadataObj),
                        Milliseconds(0)})
                       ->getStatus());
 }
@@ -480,8 +495,9 @@ TEST_F(OplogFetcherTest,
     ASSERT_EQUALS(
         ErrorCodes::OplogStartMissing,
         processSingleBatch(
-            {makeCursorResponse(0, {makeNoopOplogEntry(remoteNewerOpTime, lastFetched.value + 1)}),
-             metadataObj,
+            {concatenate(makeCursorResponse(
+                             0, {makeNoopOplogEntry(remoteNewerOpTime, lastFetched.value + 1)}),
+                         metadataObj),
              Milliseconds(0)})
             ->getStatus());
 }
@@ -489,28 +505,30 @@ TEST_F(OplogFetcherTest,
 TEST_F(OplogFetcherTest,
        MissingOpTimeInSecondDocumentOfFirstBatchCausesOplogFetcherToStopWithNoSuchKey) {
     auto metadataObj = makeOplogQueryMetadataObject(remoteNewerOpTime, rbid, 2, 2);
-    ASSERT_EQUALS(ErrorCodes::NoSuchKey,
-                  processSingleBatch(
-                      {makeCursorResponse(0,
-                                          {makeNoopOplogEntry(lastFetched),
-                                           BSON("o" << BSON("msg"
-                                                            << "oplog entry without optime"))}),
-                       metadataObj,
-                       Milliseconds(0)})
-                      ->getStatus());
+    ASSERT_EQUALS(
+        ErrorCodes::NoSuchKey,
+        processSingleBatch(
+            {concatenate(makeCursorResponse(0,
+                                            {makeNoopOplogEntry(lastFetched),
+                                             BSON("o" << BSON("msg"
+                                                              << "oplog entry without optime"))}),
+                         metadataObj),
+             Milliseconds(0)})
+            ->getStatus());
 }
 
 TEST_F(OplogFetcherTest, TimestampsNotAdvancingInBatchCausesOplogFetcherStopWithOplogOutOfOrder) {
     auto metadataObj = makeOplogQueryMetadataObject(remoteNewerOpTime, rbid, 2, 2);
-    ASSERT_EQUALS(ErrorCodes::OplogOutOfOrder,
-                  processSingleBatch({makeCursorResponse(0,
-                                                         {makeNoopOplogEntry(lastFetched),
-                                                          makeNoopOplogEntry(Seconds(1000), 1),
-                                                          makeNoopOplogEntry(Seconds(2000), 1),
-                                                          makeNoopOplogEntry(Seconds(1500), 1)}),
-                                      metadataObj,
-                                      Milliseconds(0)})
-                      ->getStatus());
+    ASSERT_EQUALS(
+        ErrorCodes::OplogOutOfOrder,
+        processSingleBatch({concatenate(makeCursorResponse(0,
+                                                           {makeNoopOplogEntry(lastFetched),
+                                                            makeNoopOplogEntry(Seconds(1000), 1),
+                                                            makeNoopOplogEntry(Seconds(2000), 1),
+                                                            makeNoopOplogEntry(Seconds(1500), 1)}),
+                                        metadataObj),
+                            Milliseconds(0)})
+            ->getStatus());
 }
 
 TEST_F(OplogFetcherTest, OplogFetcherShouldExcludeFirstDocumentInFirstBatchWhenEnqueuingDocuments) {
@@ -521,8 +539,8 @@ TEST_F(OplogFetcherTest, OplogFetcherShouldExcludeFirstDocumentInFirstBatchWhenE
     auto thirdEntry = makeNoopOplogEntry({{Seconds(789), 0}, lastFetched.opTime.getTerm()}, 300);
     Fetcher::Documents documents{firstEntry, secondEntry, thirdEntry};
 
-    auto shutdownState =
-        processSingleBatch({makeCursorResponse(0, documents), metadataObj, Milliseconds(0)});
+    auto shutdownState = processSingleBatch(
+        {concatenate(makeCursorResponse(0, documents), metadataObj), Milliseconds(0)});
 
     ASSERT_EQUALS(2U, lastEnqueuedDocuments.size());
     ASSERT_BSONOBJ_EQ(secondEntry, lastEnqueuedDocuments[0]);
@@ -559,8 +577,8 @@ TEST_F(OplogFetcherTest, OplogFetcherShouldReportErrorsThrownFromCallback) {
         return Status(ErrorCodes::InternalError, "my custom error");
     };
 
-    auto shutdownState =
-        processSingleBatch({makeCursorResponse(0, documents), metadataObj, Milliseconds(0)});
+    auto shutdownState = processSingleBatch(
+        {concatenate(makeCursorResponse(0, documents), metadataObj), Milliseconds(0)});
     ASSERT_EQ(shutdownState->getStatus(), Status(ErrorCodes::InternalError, "my custom error"));
 }
 
@@ -582,8 +600,8 @@ void OplogFetcherTest::testSyncSourceChecking(rpc::ReplSetMetadata* replMetadata
 
     dataReplicatorExternalState->shouldStopFetchingResult = true;
 
-    auto shutdownState =
-        processSingleBatch({makeCursorResponse(0, documents), metadataObj, Milliseconds(0)});
+    auto shutdownState = processSingleBatch(
+        {concatenate(makeCursorResponse(0, documents), metadataObj), Milliseconds(0)});
 
     // Sync source checking happens after we have successfully pushed the operations into
     // the buffer for the next replication phase (eg. applier).
@@ -697,7 +715,8 @@ RemoteCommandRequest OplogFetcherTest::testTwoBatchHandling() {
 
     auto metadataObj = makeOplogQueryMetadataObject(remoteNewerOpTime, rbid, 2, 2);
     processNetworkResponse(
-        {makeCursorResponse(cursorId, {firstEntry, secondEntry}), metadataObj, Milliseconds(0)},
+        {concatenate(makeCursorResponse(cursorId, {firstEntry, secondEntry}), metadataObj),
+         Milliseconds(0)},
         true);
 
     ASSERT_EQUALS(1U, lastEnqueuedDocuments.size());
diff --git a/src/mongo/db/repl/replication_coordinator_impl_heartbeat.cpp b/src/mongo/db/repl/replication_coordinator_impl_heartbeat.cpp
index 479881621eb..2b06d004d0a 100644
--- a/src/mongo/db/repl/replication_coordinator_impl_heartbeat.cpp
+++ b/src/mongo/db/repl/replication_coordinator_impl_heartbeat.cpp
@@ -149,7 +149,7 @@ void ReplicationCoordinatorImpl::_handleHeartbeatResponse(
         resp = cbData.response.data;
         responseStatus = hbResponse.initialize(resp, _topCoord->getTerm());
         StatusWith<rpc::ReplSetMetadata> replMetadata =
-            rpc::ReplSetMetadata::readFromMetadata(cbData.response.metadata);
+            rpc::ReplSetMetadata::readFromMetadata(cbData.response.data);
 
         LOG_FOR_HEARTBEATS(2) << "Received response to heartbeat (requestId: " << cbData.request.id
                               << ") from " << target << ", " << resp;
diff --git a/src/mongo/db/repl/replication_coordinator_impl_heartbeat_v1_test.cpp b/src/mongo/db/repl/replication_coordinator_impl_heartbeat_v1_test.cpp
index 61a63ca9225..5bb5c2a2ee2 100644
--- a/src/mongo/db/repl/replication_coordinator_impl_heartbeat_v1_test.cpp
+++ b/src/mongo/db/repl/replication_coordinator_impl_heartbeat_v1_test.cpp
@@ -394,10 +394,9 @@ TEST_F(ReplCoordHBV1Test, IgnoreTheContentsOfMetadataWhenItsReplicaSetIdDoesNotM
 
         rpc::ReplSetMetadata metadata(
             opTime.getTerm(), opTime, opTime, rsConfig.getConfigVersion(), unexpectedId, 1, -1);
-        BSONObjBuilder metadataBuilder;
-        metadata.writeToMetadata(&metadataBuilder).transitional_ignore();
+        uassertStatusOK(metadata.writeToMetadata(&responseBuilder));
 
-        heartbeatResponse = makeResponseStatus(responseBuilder.obj(), metadataBuilder.obj());
+        heartbeatResponse = makeResponseStatus(responseBuilder.obj());
     }
 
     // process heartbeat
diff --git a/src/mongo/db/repl/replication_coordinator_impl_test.cpp b/src/mongo/db/repl/replication_coordinator_impl_test.cpp
index 9d64861a4ab..f703624e158 100644
--- a/src/mongo/db/repl/replication_coordinator_impl_test.cpp
+++ b/src/mongo/db/repl/replication_coordinator_impl_test.cpp
@@ -384,9 +384,8 @@ TEST_F(ReplCoordTest, InitiateSucceedsWhenQuorumCheckPasses) {
     hbResp.setConfigVersion(0);
     hbResp.setAppliedOpTime(OpTime(Timestamp(100, 1), 0));
     hbResp.setDurableOpTime(OpTime(Timestamp(100, 1), 0));
-    getNet()->scheduleResponse(noi,
-                               startDate + Milliseconds(10),
-                               RemoteCommandResponse(hbResp.toBSON(), BSONObj(), Milliseconds(8)));
+    getNet()->scheduleResponse(
+        noi, startDate + Milliseconds(10), RemoteCommandResponse(hbResp.toBSON(), Milliseconds(8)));
     getNet()->runUntil(startDate + Milliseconds(10));
     getNet()->exitNetwork();
     ASSERT_EQUALS(startDate + Milliseconds(10), getNet()->now());
@@ -4521,9 +4520,8 @@ TEST_F(ReplCoordTest,
                                   << 3
                                   << "syncSourceIndex"
                                   << 1)));
-    BSONObjBuilder metadataBuilder;
-    ASSERT_OK(metadata.getValue().writeToMetadata(&metadataBuilder));
-    auto metadataObj = metadataBuilder.obj();
+    BSONObjBuilder responseBuilder;
+    ASSERT_OK(metadata.getValue().writeToMetadata(&responseBuilder));
 
     auto net = getNet();
     net->enterNetwork();
@@ -4538,7 +4536,8 @@ TEST_F(ReplCoordTest,
     hbResp.setConfigVersion(config.getConfigVersion());
     hbResp.setSetName(config.getReplSetName());
     hbResp.setState(MemberState::RS_SECONDARY);
-    net->scheduleResponse(noi, net->now(), makeResponseStatus(hbResp.toBSON(), metadataObj));
+    responseBuilder.appendElements(hbResp.toBSON());
+    net->scheduleResponse(noi, net->now(), makeResponseStatus(responseBuilder.obj()));
     net->runReadyNetworkOperations();
     net->exitNetwork();
 
@@ -4647,9 +4646,8 @@ TEST_F(ReplCoordTest, TermAndLastCommittedOpTimeUpdatedFromHeartbeatWhenArbiter)
                                   << 3
                                   << "syncSourceIndex"
                                   << 1)));
-    BSONObjBuilder metadataBuilder;
-    ASSERT_OK(metadata.getValue().writeToMetadata(&metadataBuilder));
-    auto metadataObj = metadataBuilder.obj();
+    BSONObjBuilder responseBuilder;
+    ASSERT_OK(metadata.getValue().writeToMetadata(&responseBuilder));
 
     auto net = getNet();
     net->enterNetwork();
@@ -4664,7 +4662,8 @@ TEST_F(ReplCoordTest, TermAndLastCommittedOpTimeUpdatedFromHeartbeatWhenArbiter)
     hbResp.setConfigVersion(config.getConfigVersion());
     hbResp.setSetName(config.getReplSetName());
     hbResp.setState(MemberState::RS_SECONDARY);
-    net->scheduleResponse(noi, net->now(), makeResponseStatus(hbResp.toBSON(), metadataObj));
+    responseBuilder.appendElements(hbResp.toBSON());
+    net->scheduleResponse(noi, net->now(), makeResponseStatus(responseBuilder.obj()));
     net->runReadyNetworkOperations();
     net->exitNetwork();
 
diff --git a/src/mongo/db/repl/replication_coordinator_test_fixture.cpp b/src/mongo/db/repl/replication_coordinator_test_fixture.cpp
index 456c9443276..10f1babe0f2 100644
--- a/src/mongo/db/repl/replication_coordinator_test_fixture.cpp
+++ b/src/mongo/db/repl/replication_coordinator_test_fixture.cpp
@@ -212,15 +212,8 @@ void ReplCoordTest::assertStartSuccess(const BSONObj& configDoc, const HostAndPo
 
 executor::RemoteCommandResponse ReplCoordTest::makeResponseStatus(const BSONObj& doc,
                                                                   Milliseconds millis) {
-    return makeResponseStatus(doc, BSONObj(), millis);
-}
-
-executor::RemoteCommandResponse ReplCoordTest::makeResponseStatus(const BSONObj& doc,
-                                                                  const BSONObj& metadata,
-                                                                  Milliseconds millis) {
-    log() << "Responding with " << doc << " (metadata: " << metadata << "; elapsed: " << millis
-          << ")";
-    return RemoteCommandResponse(doc, metadata, millis);
+    log() << "Responding with " << doc << " (elapsed: " << millis << ")";
+    return RemoteCommandResponse(doc, millis);
 }
 
 void ReplCoordTest::simulateEnoughHeartbeatsForAllNodesUp() {
diff --git a/src/mongo/db/repl/replication_coordinator_test_fixture.h b/src/mongo/db/repl/replication_coordinator_test_fixture.h
index b5718a65a70..2e3732a4caa 100644
--- a/src/mongo/db/repl/replication_coordinator_test_fixture.h
+++ b/src/mongo/db/repl/replication_coordinator_test_fixture.h
@@ -65,13 +65,6 @@ public:
         const BSONObj& doc, Milliseconds millis = Milliseconds(0));
 
     /**
-     * Makes a command response with the given "doc" response, metadata and optional elapsed time
-     * "millis".
-     */
-    static executor::RemoteCommandResponse makeResponseStatus(
-        const BSONObj& doc, const BSONObj& metadata, Milliseconds millis = Milliseconds(0));
-
-    /**
      * Constructs a ReplSetConfig from the given BSON, or raises a test failure exception.
      */
     static ReplSetConfig assertMakeRSConfig(const BSONObj& configBSON);
diff --git a/src/mongo/db/repl/reporter_test.cpp b/src/mongo/db/repl/reporter_test.cpp
index 5fb620d5252..8c6ac958c16 100644
--- a/src/mongo/db/repl/reporter_test.cpp
+++ b/src/mongo/db/repl/reporter_test.cpp
@@ -331,7 +331,7 @@ TEST_F(ReporterTestNoTriggerAtSetUp, IsNotActiveAfterUpdatePositionTimeoutExpire
     // Schedule a response to the updatePosition command at a time that exceeds the timeout. Then
     // make sure the reporter shut down due to a remote command timeout.
     auto updatePosRequest = net->getNextReadyRequest();
-    RemoteCommandResponse response(BSON("ok" << 1), BSONObj(), Milliseconds(0));
+    RemoteCommandResponse response(BSON("ok" << 1), Milliseconds(0));
     executor::TaskExecutor::ResponseStatus responseStatus(response);
     net->scheduleResponse(
         updatePosRequest, net->now() + updatePositionTimeout + Milliseconds(1), responseStatus);
diff --git a/src/mongo/db/repl/scatter_gather_test.cpp b/src/mongo/db/repl/scatter_gather_test.cpp
index 1d5a32b4895..8d1c8f480fb 100644
--- a/src/mongo/db/repl/scatter_gather_test.cpp
+++ b/src/mongo/db/repl/scatter_gather_test.cpp
@@ -165,21 +165,18 @@ TEST_F(ScatterGatherTest, DeleteAlgorithmAfterItHasCompleted) {
     NetworkInterfaceMock* net = getNet();
     net->enterNetwork();
     NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
-    net->scheduleResponse(noi,
-                          net->now() + Seconds(2),
-                          (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+    net->scheduleResponse(
+        noi, net->now() + Seconds(2), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
 
     noi = net->getNextReadyRequest();
-    net->scheduleResponse(noi,
-                          net->now() + Seconds(2),
-                          (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+    net->scheduleResponse(
+        noi, net->now() + Seconds(2), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
 
     noi = net->getNextReadyRequest();
-    net->scheduleResponse(noi,
-                          net->now() + Seconds(5),
-                          (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+    net->scheduleResponse(
+        noi, net->now() + Seconds(5), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
 
     net->runUntil(net->now() + Seconds(2));
@@ -208,21 +205,19 @@ TEST_F(ScatterGatherTest, DeleteAlgorithmBeforeItCompletes) {
     net->enterNetwork();
     NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
     net->scheduleResponse(
-        noi, net->now(), (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+        noi, net->now(), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
     // Get and process the response from the first node immediately.
     net->runReadyNetworkOperations();
 
     noi = net->getNextReadyRequest();
-    net->scheduleResponse(noi,
-                          net->now() + Seconds(2),
-                          (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+    net->scheduleResponse(
+        noi, net->now() + Seconds(2), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
 
     noi = net->getNextReadyRequest();
-    net->scheduleResponse(noi,
-                          net->now() + Seconds(5),
-                          (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+    net->scheduleResponse(
+        noi, net->now() + Seconds(5), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
 
     sga.reset();
@@ -248,9 +243,8 @@ TEST_F(ScatterGatherTest, DeleteAlgorithmAfterCancel) {
     NetworkInterfaceMock* net = getNet();
     net->enterNetwork();
     NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
-    net->scheduleResponse(noi,
-                          net->now() + Seconds(2),
-                          (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+    net->scheduleResponse(
+        noi, net->now() + Seconds(2), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
 
     // Cancel the runner so following responses won't change the result. All pending requests
@@ -347,21 +341,18 @@ TEST_F(ScatterGatherTest, DoNotProcessMoreThanSufficientResponses) {
     NetworkInterfaceMock* net = getNet();
     net->enterNetwork();
     NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
-    net->scheduleResponse(noi,
-                          net->now() + Seconds(2),
-                          (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+    net->scheduleResponse(
+        noi, net->now() + Seconds(2), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
 
     noi = net->getNextReadyRequest();
-    net->scheduleResponse(noi,
-                          net->now() + Seconds(2),
-                          (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+    net->scheduleResponse(
+        noi, net->now() + Seconds(2), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
 
     noi = net->getNextReadyRequest();
-    net->scheduleResponse(noi,
-                          net->now() + Seconds(5),
-                          (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+    net->scheduleResponse(
+        noi, net->now() + Seconds(5), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
 
     net->runUntil(net->now() + Seconds(2));
@@ -390,9 +381,8 @@ TEST_F(ScatterGatherTest, AlgorithmProcessesCallbackCanceledResponse) {
     NetworkInterfaceMock* net = getNet();
     net->enterNetwork();
     NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
-    net->scheduleResponse(noi,
-                          net->now() + Seconds(2),
-                          (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+    net->scheduleResponse(
+        noi, net->now() + Seconds(2), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     ASSERT_FALSE(ranCompletion);
 
     noi = net->getNextReadyRequest();
@@ -493,7 +483,7 @@ TEST_F(ScatterGatherTest, SuccessfulScatterGatherViaRun) {
     net->enterNetwork();
     NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
     net->scheduleResponse(
-        noi, net->now(), (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+        noi, net->now(), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     net->runReadyNetworkOperations();
 
     noi = net->getNextReadyRequest();
@@ -502,7 +492,7 @@ TEST_F(ScatterGatherTest, SuccessfulScatterGatherViaRun) {
 
     noi = net->getNextReadyRequest();
     net->scheduleResponse(
-        noi, net->now(), (RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
+        noi, net->now(), (RemoteCommandResponse(BSON("ok" << 1), Milliseconds(10))));
     net->runReadyNetworkOperations();
     net->exitNetwork();
 
diff --git a/src/mongo/db/repl/vote_requester_test.cpp b/src/mongo/db/repl/vote_requester_test.cpp
index 74374d3ad36..9a11270e577 100644
--- a/src/mongo/db/repl/vote_requester_test.cpp
+++ b/src/mongo/db/repl/vote_requester_test.cpp
@@ -153,7 +153,7 @@ protected:
         ReplSetRequestVotesResponse response;
         response.setVoteGranted(true);
         response.setTerm(1);
-        return RemoteCommandResponse(response.toBSON(), BSONObj(), Milliseconds(10));
+        return RemoteCommandResponse(response.toBSON(), Milliseconds(10));
     }
 
     RemoteCommandResponse votedYesStatusNotOkBecauseFailedToStoreLastVote() {
@@ -164,7 +164,7 @@ protected:
         response.addToBSON(&result);
         auto status = Status(ErrorCodes::InterruptedDueToStepDown, "operation was interrupted");
         CommandHelpers::appendCommandStatusNoThrow(result, status);
-        return RemoteCommandResponse(result.obj(), BSONObj(), Milliseconds(10));
+        return RemoteCommandResponse(result.obj(), Milliseconds(10));
     }
 
     RemoteCommandResponse votedNoBecauseConfigVersionDoesNotMatch() {
@@ -172,7 +172,7 @@ protected:
         response.setVoteGranted(false);
         response.setTerm(1);
         response.setReason("candidate's config version differs from mine");
-        return RemoteCommandResponse(response.toBSON(), BSONObj(), Milliseconds(10));
+        return RemoteCommandResponse(response.toBSON(), Milliseconds(10));
     }
 
     RemoteCommandResponse votedNoBecauseSetNameDiffers() {
@@ -180,7 +180,7 @@ protected:
         response.setVoteGranted(false);
         response.setTerm(1);
         response.setReason("candidate's set name differs from mine");
-        return RemoteCommandResponse(response.toBSON(), BSONObj(), Milliseconds(10));
+        return RemoteCommandResponse(response.toBSON(), Milliseconds(10));
     }
 
     RemoteCommandResponse votedNoBecauseLastOpTimeIsGreater() {
@@ -188,7 +188,7 @@ protected:
         response.setVoteGranted(false);
         response.setTerm(1);
         response.setReason("candidate's data is staler than mine");
-        return RemoteCommandResponse(response.toBSON(), BSONObj(), Milliseconds(10));
+        return RemoteCommandResponse(response.toBSON(), Milliseconds(10));
     }
 
     RemoteCommandResponse votedNoBecauseTermIsGreater() {
@@ -196,7 +196,7 @@ protected:
         response.setVoteGranted(false);
         response.setTerm(3);
         response.setReason("candidate's term is lower than mine");
-        return RemoteCommandResponse(response.toBSON(), BSONObj(), Milliseconds(10));
+        return RemoteCommandResponse(response.toBSON(), Milliseconds(10));
     }
 
     RemoteCommandResponse votedNoBecauseAlreadyVoted() {
@@ -204,7 +204,7 @@ protected:
         response.setVoteGranted(false);
         response.setTerm(2);
         response.setReason("already voted for another candidate this term");
-        return RemoteCommandResponse(response.toBSON(), BSONObj(), Milliseconds(10));
+        return RemoteCommandResponse(response.toBSON(), Milliseconds(10));
     }
 
     std::unique_ptr<VoteRequester::Algorithm> _requester;
diff --git a/src/mongo/db/s/config/sharding_catalog_manager_shard_operations.cpp b/src/mongo/db/s/config/sharding_catalog_manager_shard_operations.cpp
index 9992f06acb5..7ef70b27738 100644
--- a/src/mongo/db/s/config/sharding_catalog_manager_shard_operations.cpp
+++ b/src/mongo/db/s/config/sharding_catalog_manager_shard_operations.cpp
@@ -198,7 +198,6 @@ StatusWith<Shard::CommandResponse> ShardingCatalogManager::_runCommandForAddShar
 
     return Shard::CommandResponse(std::move(host),
                                   std::move(result),
-                                  response.metadata.getOwned(),
                                   std::move(commandStatus),
                                   std::move(writeConcernStatus));
 }
diff --git a/src/mongo/db/s/migration_source_manager.cpp b/src/mongo/db/s/migration_source_manager.cpp
index d49a85ad625..d6bd884ba26 100644
--- a/src/mongo/db/s/migration_source_manager.cpp
+++ b/src/mongo/db/s/migration_source_manager.cpp
@@ -545,9 +545,7 @@ Status MigrationSourceManager::commitChunkMetadataOnConfig(OperationContext* opC
             severe() << "The current config server opTime is " << Grid::get(opCtx)->configOpTime();
             severe() << "The commit response came from "
                      << redact(commitChunkMigrationResponse.getValue().hostAndPort->toString())
-                     << " and contained:";
-            severe() << "  metadata: "
-                     << redact(commitChunkMigrationResponse.getValue().metadata.toString());
+                     << " and contained";
             severe() << "  response: "
                      << redact(commitChunkMigrationResponse.getValue().response.toString());
 
diff --git a/src/mongo/db/service_entry_point_common.cpp b/src/mongo/db/service_entry_point_common.cpp
index 16a4671961f..0f0581104e9 100644
--- a/src/mongo/db/service_entry_point_common.cpp
+++ b/src/mongo/db/service_entry_point_common.cpp
@@ -213,7 +213,7 @@ void generateErrorResponse(OperationContext* opCtx,
     // so we need to reset it to a clean state just to be sure.
     replyBuilder->reset();
     replyBuilder->setCommandReply(exception.toStatus(), extraFields);
-    replyBuilder->setMetadata(replyMetadata);
+    replyBuilder->getBodyBuilder().appendElements(replyMetadata);
 }
 
 BSONObj getErrorLabels(const boost::optional<OperationSessionInfoFromClient>& sessionOptions,
@@ -571,15 +571,10 @@ bool runCommandImpl(OperationContext* opCtx,
         }
     }
 
-    BSONObjBuilder metadataBob;
-    appendReplyMetadata(opCtx, request, &metadataBob);
+    auto commandBodyBob = replyBuilder->getBodyBuilder();
+    appendReplyMetadata(opCtx, request, &commandBodyBob);
+    appendClusterAndOperationTime(opCtx, &commandBodyBob, &commandBodyBob, startOperationTime);
 
-    {
-        auto commandBodyBob = replyBuilder->getBodyBuilder();
-        appendClusterAndOperationTime(opCtx, &commandBodyBob, &metadataBob, startOperationTime);
-    }
-
-    replyBuilder->setMetadata(metadataBob.obj());
     return ok;
 }
 
diff --git a/src/mongo/dbtests/mock/mock_remote_db_server.cpp b/src/mongo/dbtests/mock/mock_remote_db_server.cpp
index 0c18b18bfb1..baa35e0f8f6 100644
--- a/src/mongo/dbtests/mock/mock_remote_db_server.cpp
+++ b/src/mongo/dbtests/mock/mock_remote_db_server.cpp
@@ -163,10 +163,7 @@ rpc::UniqueReply MockRemoteDBServer::runCommand(InstanceID id, const OpMsgReques
 
     // We need to construct a reply message - it will always be read through a view so it
     // doesn't matter whether we use OpMsgReplyBuilder or LegacyReplyBuilder
-    auto message = rpc::OpMsgReplyBuilder{}
-                       .setCommandReply(reply)
-                       .setMetadata(rpc::makeEmptyMetadata())
-                       .done();
+    auto message = rpc::OpMsgReplyBuilder{}.setCommandReply(reply).done();
     auto replyView = stdx::make_unique<rpc::OpMsgReply>(&message);
     return rpc::UniqueReply(std::move(message), std::move(replyView));
 }
diff --git a/src/mongo/executor/network_interface_mock.cpp b/src/mongo/executor/network_interface_mock.cpp
index 42cda1b4005..942d3795eea 100644
--- a/src/mongo/executor/network_interface_mock.cpp
+++ b/src/mongo/executor/network_interface_mock.cpp
@@ -326,7 +326,7 @@ void NetworkInterfaceMock::scheduleResponse(NetworkOperationIterator noi,
     if (_metadataHook && response.isOK()) {
         _metadataHook
             ->readReplyMetadata(
-                noi->getRequest().opCtx, noi->getRequest().target.toString(), response.metadata)
+                noi->getRequest().opCtx, noi->getRequest().target.toString(), response.data)
             .transitional_ignore();
     }
 
@@ -335,8 +335,7 @@ void NetworkInterfaceMock::scheduleResponse(NetworkOperationIterator noi,
 }
 
 RemoteCommandRequest NetworkInterfaceMock::scheduleSuccessfulResponse(const BSONObj& response) {
-    BSONObj metadata;
-    return scheduleSuccessfulResponse(RemoteCommandResponse(response, metadata, Milliseconds(0)));
+    return scheduleSuccessfulResponse(RemoteCommandResponse(response, Milliseconds(0)));
 }
 
 RemoteCommandRequest NetworkInterfaceMock::scheduleSuccessfulResponse(
@@ -479,7 +478,7 @@ void NetworkInterfaceMock::_connectThenEnqueueOperation_inlock(const HostAndPort
 
     auto handshakeReply = (handshakeReplyIter != std::end(_handshakeReplies))
         ? handshakeReplyIter->second
-        : RemoteCommandResponse(BSONObj(), BSONObj(), Milliseconds(0));
+        : RemoteCommandResponse(BSONObj(), Milliseconds(0));
 
     auto valid = _hook->validateHost(target, op.getRequest().cmdObj, handshakeReply);
     if (!valid.isOK()) {
diff --git a/src/mongo/executor/network_interface_mock_test.cpp b/src/mongo/executor/network_interface_mock_test.cpp
index a09ed4aeac0..ef7aebbdb9a 100644
--- a/src/mongo/executor/network_interface_mock_test.cpp
+++ b/src/mongo/executor/network_interface_mock_test.cpp
@@ -116,8 +116,8 @@ TEST_F(NetworkInterfaceMockTest, ConnectionHook) {
     RemoteCommandResponse expectedResponse{BSON("foo"
                                                 << "bar"
                                                 << "baz"
-                                                << "garply"),
-                                           BSON("bar"
+                                                << "garply"
+                                                << "bar"
                                                 << "baz"),
                                            Milliseconds(30)};
 
@@ -125,8 +125,7 @@ TEST_F(NetworkInterfaceMockTest, ConnectionHook) {
     auto isMasterReplyData = BSON("iamyour"
                                   << "father");
 
-    RemoteCommandResponse isMasterReply{
-        isMasterReplyData.copy(), BSON("blah" << 2), Milliseconds(20)};
+    RemoteCommandResponse isMasterReply{isMasterReplyData.copy(), Milliseconds(20)};
 
     net().setHandshakeReplyForHost(testHost(), std::move(isMasterReply));
 
@@ -166,7 +165,6 @@ TEST_F(NetworkInterfaceMockTest, ConnectionHook) {
         testHost(), "testDB", BSON("test" << 1), rpc::makeEmptyMetadata(), nullptr};
     RemoteCommandResponse actualResponseExpected{BSON("1212121212"
                                                       << "12121212121212"),
-                                                 BSONObj(),
                                                  Milliseconds(0)};
 
     ASSERT_OK(net().startCommand(cb, actualCommandExpected, [&](RemoteCommandResponse resp) {
diff --git a/src/mongo/executor/network_interface_tl.cpp b/src/mongo/executor/network_interface_tl.cpp
index 923d25f565e..3c885feab5f 100644
--- a/src/mongo/executor/network_interface_tl.cpp
+++ b/src/mongo/executor/network_interface_tl.cpp
@@ -360,7 +360,7 @@ Future<RemoteCommandResponse> NetworkInterfaceTL::_onAcquireConn(
             if (_metadataHook && response.status.isOK()) {
                 auto target = state->conn->getHostAndPort().toString();
                 response.status =
-                    _metadataHook->readReplyMetadata(nullptr, std::move(target), response.metadata);
+                    _metadataHook->readReplyMetadata(nullptr, std::move(target), response.data);
             }
 
             return RemoteCommandResponse(std::move(response));
diff --git a/src/mongo/executor/network_test_env.cpp b/src/mongo/executor/network_test_env.cpp
index bc782c8ce8c..d60bd0d4fa7 100644
--- a/src/mongo/executor/network_test_env.cpp
+++ b/src/mongo/executor/network_test_env.cpp
@@ -52,7 +52,7 @@ void NetworkTestEnv::onCommand(OnCommandFunction func) {
     if (resultStatus.isOK()) {
         BSONObjBuilder result(std::move(resultStatus.getValue()));
         CommandHelpers::appendCommandStatusNoThrow(result, resultStatus.getStatus());
-        const RemoteCommandResponse response(result.obj(), BSONObj(), Milliseconds(1));
+        const RemoteCommandResponse response(result.obj(), Milliseconds(1));
 
         _mockNetwork->scheduleResponse(noi, _mockNetwork->now(), response);
     } else {
@@ -75,8 +75,7 @@ void NetworkTestEnv::onCommandWithMetadata(OnCommandWithMetadataFunction func) {
     if (cmdResponseStatus.isOK()) {
         BSONObjBuilder result(std::move(cmdResponseStatus.data));
         CommandHelpers::appendCommandStatusNoThrow(result, cmdResponseStatus.status);
-        const RemoteCommandResponse response(
-            result.obj(), cmdResponseStatus.metadata, Milliseconds(1));
+        const RemoteCommandResponse response(result.obj(), Milliseconds(1));
 
         _mockNetwork->scheduleResponse(noi, _mockNetwork->now(), response);
     } else {
@@ -128,10 +127,10 @@ void NetworkTestEnv::onFindWithMetadataCommand(OnFindCommandWithMetadataFunction
 
         const NamespaceString nss =
             NamespaceString(request.dbname, request.cmdObj.firstElement().String());
-        BSONObjBuilder resultBuilder;
+        BSONObjBuilder resultBuilder(std::move(metadata));
         appendCursorResponseObject(0LL, nss.toString(), arr.arr(), &resultBuilder);
 
-        return RemoteCommandResponse(resultBuilder.obj(), metadata, Milliseconds(1));
+        return RemoteCommandResponse(resultBuilder.obj(), Milliseconds(1));
     });
 }
 
diff --git a/src/mongo/executor/remote_command_response.cpp b/src/mongo/executor/remote_command_response.cpp
index 4fb8af3ccf2..e40917843cb 100644
--- a/src/mongo/executor/remote_command_response.cpp
+++ b/src/mongo/executor/remote_command_response.cpp
@@ -54,38 +54,29 @@ RemoteCommandResponse::RemoteCommandResponse(Status s, Milliseconds millis)
     invariant(!isOK());
 };
 
-RemoteCommandResponse::RemoteCommandResponse(BSONObj dataObj,
-                                             BSONObj metadataObj,
-                                             Milliseconds millis)
-    : data(std::move(dataObj)), metadata(std::move(metadataObj)), elapsedMillis(millis) {
+RemoteCommandResponse::RemoteCommandResponse(BSONObj dataObj, Milliseconds millis)
+    : data(std::move(dataObj)), elapsedMillis(millis) {
     // The buffer backing the default empty BSONObj has static duration so it is effectively
     // owned.
     invariant(data.isOwned() || data.objdata() == BSONObj().objdata());
-    invariant(metadata.isOwned() || metadata.objdata() == BSONObj().objdata());
 };
 
 RemoteCommandResponse::RemoteCommandResponse(Message messageArg,
                                              BSONObj dataObj,
-                                             BSONObj metadataObj,
                                              Milliseconds millis)
     : message(std::make_shared<const Message>(std::move(messageArg))),
       data(std::move(dataObj)),
-      metadata(std::move(metadataObj)),
       elapsedMillis(millis) {
     if (!data.isOwned()) {
         data.shareOwnershipWith(message->sharedBuffer());
     }
-    if (!metadata.isOwned()) {
-        metadata.shareOwnershipWith(message->sharedBuffer());
-    }
 }
 
 // TODO(amidvidy): we currently discard output docs when we use this constructor. We should
 // have RCR hold those too, but we need more machinery before that is possible.
 RemoteCommandResponse::RemoteCommandResponse(const rpc::ReplyInterface& rpcReply,
                                              Milliseconds millis)
-    : RemoteCommandResponse(rpcReply.getCommandReply(), rpcReply.getMetadata(), std::move(millis)) {
-}
+    : RemoteCommandResponse(rpcReply.getCommandReply(), std::move(millis)) {}
 
 bool RemoteCommandResponse::isOK() const {
     return status.isOK();
@@ -101,8 +92,7 @@ bool RemoteCommandResponse::operator==(const RemoteCommandResponse& rhs) const {
         return true;
     }
     SimpleBSONObjComparator bsonComparator;
-    return bsonComparator.evaluate(data == rhs.data) &&
-        bsonComparator.evaluate(metadata == rhs.metadata) && elapsedMillis == rhs.elapsedMillis;
+    return bsonComparator.evaluate(data == rhs.data) && elapsedMillis == rhs.elapsedMillis;
 }
 
 bool RemoteCommandResponse::operator!=(const RemoteCommandResponse& rhs) const {
diff --git a/src/mongo/executor/remote_command_response.h b/src/mongo/executor/remote_command_response.h
index 0dd51f68ba8..894ca915e7d 100644
--- a/src/mongo/executor/remote_command_response.h
+++ b/src/mongo/executor/remote_command_response.h
@@ -61,12 +61,9 @@ struct RemoteCommandResponse {
 
     RemoteCommandResponse(Status s, Milliseconds millis);
 
-    RemoteCommandResponse(BSONObj dataObj, BSONObj metadataObj, Milliseconds millis);
+    RemoteCommandResponse(BSONObj dataObj, Milliseconds millis);
 
-    RemoteCommandResponse(Message messageArg,
-                          BSONObj dataObj,
-                          BSONObj metadataObj,
-                          Milliseconds millis);
+    RemoteCommandResponse(Message messageArg, BSONObj dataObj, Milliseconds millis);
 
     RemoteCommandResponse(const rpc::ReplyInterface& rpcReply, Milliseconds millis);
 
@@ -79,7 +76,6 @@ struct RemoteCommandResponse {
 
     std::shared_ptr<const Message> message;  // May be null.
     BSONObj data;                            // Always owned. May point into message.
-    BSONObj metadata;                        // Always owned. May point into message.
     boost::optional<Milliseconds> elapsedMillis;
     Status status = Status::OK();
 };
diff --git a/src/mongo/rpc/legacy_reply.cpp b/src/mongo/rpc/legacy_reply.cpp
index d21b880e60c..c6ba4bfbb02 100644
--- a/src/mongo/rpc/legacy_reply.cpp
+++ b/src/mongo/rpc/legacy_reply.cpp
@@ -102,10 +102,6 @@ LegacyReply::LegacyReply(const Message* message) {
     return;
 }
 
-const BSONObj& LegacyReply::getMetadata() const {
-    return _commandReply;
-}
-
 const BSONObj& LegacyReply::getCommandReply() const {
     return _commandReply;
 }
diff --git a/src/mongo/rpc/legacy_reply.h b/src/mongo/rpc/legacy_reply.h
index f283bb954ec..b428319d5a7 100644
--- a/src/mongo/rpc/legacy_reply.h
+++ b/src/mongo/rpc/legacy_reply.h
@@ -41,7 +41,7 @@ namespace rpc {
 /**
  * Immutable view of an OP_REPLY legacy-style command reply.
  */
-class LegacyReply : public ReplyInterface {
+class LegacyReply final : public ReplyInterface {
 public:
     /**
      * Construct a Reply from a Message.
@@ -50,12 +50,6 @@ public:
     explicit LegacyReply(const Message* message);
 
     /**
-     * Accessor for the metadata object. Metadata is generally used for information
-     * that is independent of any specific command, e.g. auditing information.
-     */
-    const BSONObj& getMetadata() const final;
-
-    /**
      * The result of executing the command.
      */
     const BSONObj& getCommandReply() const final;
diff --git a/src/mongo/rpc/legacy_reply_builder.cpp b/src/mongo/rpc/legacy_reply_builder.cpp
index 78663e9f75f..1d88eb96aa5 100644
--- a/src/mongo/rpc/legacy_reply_builder.cpp
+++ b/src/mongo/rpc/legacy_reply_builder.cpp
@@ -54,7 +54,7 @@ LegacyReplyBuilder::~LegacyReplyBuilder() {}
 
 LegacyReplyBuilder& LegacyReplyBuilder::setCommandReply(Status nonOKStatus,
                                                         BSONObj extraErrorInfo) {
-    invariant(_state == State::kCommandReply);
+    invariant(!_haveCommandReply);
     if (nonOKStatus == ErrorCodes::StaleConfig) {
         _staleConfigError = true;
 
@@ -77,32 +77,25 @@ LegacyReplyBuilder& LegacyReplyBuilder::setCommandReply(Status nonOKStatus,
 }
 
 LegacyReplyBuilder& LegacyReplyBuilder::setRawCommandReply(const BSONObj& commandReply) {
-    invariant(_state == State::kCommandReply);
+    invariant(!_haveCommandReply);
+    _bodyOffset = _builder.len();
     commandReply.appendSelfToBufBuilder(_builder);
-    _state = State::kMetadata;
+    _haveCommandReply = true;
     return *this;
 }
 
 BSONObjBuilder LegacyReplyBuilder::getBodyBuilder() {
-    if (_state == State::kCommandReply) {
+    if (!_haveCommandReply) {
         auto bob = BSONObjBuilder(_builder);
         _bodyOffset = bob.offset();
-        _state = State::kMetadata;
+        _haveCommandReply = true;
         return bob;
     }
 
-    invariant(_state == State::kMetadata);
     invariant(_bodyOffset);
     return BSONObjBuilder(BSONObjBuilder::ResumeBuildingTag{}, _builder, _bodyOffset);
 }
 
-LegacyReplyBuilder& LegacyReplyBuilder::setMetadata(const BSONObj& metadata) {
-    invariant(_state == State::kMetadata);
-    BSONObjBuilder(BSONObjBuilder::ResumeBuildingTag(), _builder, sizeof(QueryResult::Value))
-        .appendElements(metadata);
-    _state = State::kOutputDocs;
-    return *this;
-}
 
 Protocol LegacyReplyBuilder::getProtocol() const {
     return rpc::Protocol::kOpQuery;
@@ -116,20 +109,20 @@ void LegacyReplyBuilder::reserveBytes(const std::size_t bytes) {
 void LegacyReplyBuilder::reset() {
     // If we are in State::kMetadata, we are already in the 'start' state, so by
     // immediately returning, we save a heap allocation.
-    if (_state == State::kCommandReply) {
+    if (!_haveCommandReply) {
         return;
     }
     _builder.reset();
     _builder.skip(sizeof(QueryResult::Value));
     _message.reset();
-    _state = State::kCommandReply;
+    _haveCommandReply = false;
     _staleConfigError = false;
     _bodyOffset = 0;
 }
 
 
 Message LegacyReplyBuilder::done() {
-    invariant(_state == State::kOutputDocs);
+    invariant(_haveCommandReply);
 
     QueryResult::View qr = _builder.buf();
 
@@ -148,7 +141,6 @@ Message LegacyReplyBuilder::done() {
 
     _message.setData(_builder.release());
 
-    _state = State::kDone;
     return std::move(_message);
 }
 
diff --git a/src/mongo/rpc/legacy_reply_builder.h b/src/mongo/rpc/legacy_reply_builder.h
index 4f3128bb2be..3c90dc7db4f 100644
--- a/src/mongo/rpc/legacy_reply_builder.h
+++ b/src/mongo/rpc/legacy_reply_builder.h
@@ -54,8 +54,6 @@ public:
 
     BSONObjBuilder getBodyBuilder() final;
 
-    LegacyReplyBuilder& setMetadata(const BSONObj& metadata) final;
-
     void reset() final;
 
     Message done() final;
@@ -65,14 +63,12 @@ public:
     void reserveBytes(const std::size_t bytes) final;
 
 private:
-    enum class State { kMetadata, kCommandReply, kOutputDocs, kDone };
-
-    BufBuilder _builder{};
+    BufBuilder _builder;
     std::size_t _bodyOffset = 0;
     Message _message;
-    State _state{State::kCommandReply};
+    bool _haveCommandReply = false;
     // For stale config errors we need to set the correct ResultFlag.
-    bool _staleConfigError{false};
+    bool _staleConfigError = false;
 };
 
 }  // namespace rpc
diff --git a/src/mongo/rpc/op_msg_rpc_impls.h b/src/mongo/rpc/op_msg_rpc_impls.h
index b16a9a7c0cd..ab09ffc3a2d 100644
--- a/src/mongo/rpc/op_msg_rpc_impls.h
+++ b/src/mongo/rpc/op_msg_rpc_impls.h
@@ -39,9 +39,6 @@ class OpMsgReply final : public rpc::ReplyInterface {
 public:
     explicit OpMsgReply(const Message* message) : _msg(OpMsg::parseOwned(*message)) {}
     explicit OpMsgReply(OpMsg msg) : _msg(std::move(msg)) {}
-    const BSONObj& getMetadata() const override {
-        return _msg.body;
-    }
     const BSONObj& getCommandReply() const override {
         return _msg.body;
     }
@@ -68,10 +65,6 @@ public:
     OpMsgBuilder::DocSequenceBuilder getDocSequenceBuilder(StringData name) override {
         return _builder.beginDocSequence(name);
     }
-    ReplyBuilderInterface& setMetadata(const BSONObj& metadata) override {
-        _builder.resumeBody().appendElements(metadata);
-        return *this;
-    }
     rpc::Protocol getProtocol() const override {
         return rpc::Protocol::kOpMsg;
     }
diff --git a/src/mongo/rpc/reply_builder_interface.h b/src/mongo/rpc/reply_builder_interface.h
index 64a8cab8891..e8ba5383090 100644
--- a/src/mongo/rpc/reply_builder_interface.h
+++ b/src/mongo/rpc/reply_builder_interface.h
@@ -75,8 +75,6 @@ public:
         uasserted(50875, "Only OpMsg may use document sequences");
     }
 
-    virtual ReplyBuilderInterface& setMetadata(const BSONObj& metadata) = 0;
-
     /**
      * Sets the reply for this command. If an engaged StatusWith<BSONObj> is passed, the command
      * reply will be set to the contained BSONObj, augmented with the element {ok, 1.0} if it
diff --git a/src/mongo/rpc/reply_builder_test.cpp b/src/mongo/rpc/reply_builder_test.cpp
index dd0d36a5739..2a15f519bdf 100644
--- a/src/mongo/rpc/reply_builder_test.cpp
+++ b/src/mongo/rpc/reply_builder_test.cpp
@@ -125,7 +125,7 @@ TEST(LegacyReplyBuilder, CommandError) {
     const BSONObj extraObj = extra.obj();
     rpc::LegacyReplyBuilder replyBuilder;
     replyBuilder.setCommandReply(status, extraObj);
-    replyBuilder.setMetadata(metadata);
+    replyBuilder.getBodyBuilder().appendElements(metadata);
     auto msg = replyBuilder.done();
 
     rpc::LegacyReply parsed(&msg);
@@ -136,7 +136,6 @@ TEST(LegacyReplyBuilder, CommandError) {
         return unifiedBuilder.obj();
     }());
 
-    ASSERT_BSONOBJ_EQ(parsed.getMetadata(), body);
     ASSERT_BSONOBJ_EQ(parsed.getCommandReply(), body);
 }
 
@@ -149,7 +148,7 @@ TEST(OpMsgReplyBuilder, CommandError) {
     const BSONObj extraObj = extra.obj();
     rpc::OpMsgReplyBuilder replyBuilder;
     replyBuilder.setCommandReply(status, extraObj);
-    replyBuilder.setMetadata(metadata);
+    replyBuilder.getBodyBuilder().appendElements(metadata);
     auto msg = replyBuilder.done();
 
     rpc::OpMsgReply parsed(&msg);
@@ -160,7 +159,6 @@ TEST(OpMsgReplyBuilder, CommandError) {
         return unifiedBuilder.obj();
     }());
 
-    ASSERT_BSONOBJ_EQ(parsed.getMetadata(), body);
     ASSERT_BSONOBJ_EQ(parsed.getCommandReply(), body);
 }
 
@@ -170,7 +168,7 @@ void testRoundTrip(rpc::ReplyBuilderInterface& replyBuilder, bool unifiedBodyAnd
     auto commandReply = buildEmptyCommand();
 
     replyBuilder.setCommandReply(commandReply);
-    replyBuilder.setMetadata(metadata);
+    replyBuilder.getBodyBuilder().appendElements(metadata);
 
     auto msg = replyBuilder.done();
 
@@ -184,10 +182,8 @@ void testRoundTrip(rpc::ReplyBuilderInterface& replyBuilder, bool unifiedBodyAnd
         }());
 
         ASSERT_BSONOBJ_EQ(parsed.getCommandReply(), body);
-        ASSERT_BSONOBJ_EQ(parsed.getMetadata(), body);
     } else {
         ASSERT_BSONOBJ_EQ(parsed.getCommandReply(), commandReply);
-        ASSERT_BSONOBJ_EQ(parsed.getMetadata(), metadata);
     }
 }
 
@@ -198,7 +194,7 @@ void testErrors(rpc::ReplyBuilderInterface& replyBuilder) {
     const auto status = Status(ErrorExtraInfoExample(123), "Why does this keep failing!");
 
     replyBuilder.setCommandReply(status);
-    replyBuilder.setMetadata(buildMetadata());
+    replyBuilder.getBodyBuilder().appendElements(buildMetadata());
 
     const auto msg = replyBuilder.done();
 
diff --git a/src/mongo/rpc/reply_interface.h b/src/mongo/rpc/reply_interface.h
index a5e72255d6e..c51fb686459 100644
--- a/src/mongo/rpc/reply_interface.h
+++ b/src/mongo/rpc/reply_interface.h
@@ -47,12 +47,6 @@ public:
     virtual ~ReplyInterface() = default;
 
     /**
-     * Accessor for the metadata object. Metadata is generally used for information
-     * that is independent of any specific command, e.g. auditing information.
-     */
-    virtual const BSONObj& getMetadata() const = 0;
-
-    /**
      * The result of executing the command.
      */
     virtual const BSONObj& getCommandReply() const = 0;
diff --git a/src/mongo/s/client/rs_local_client.cpp b/src/mongo/s/client/rs_local_client.cpp
index a4cf1810b3d..21888c8fc1c 100644
--- a/src/mongo/s/client/rs_local_client.cpp
+++ b/src/mongo/s/client/rs_local_client.cpp
@@ -87,7 +87,6 @@ StatusWith<Shard::CommandResponse> RSLocalClient::runCommandOnce(OperationContex
         auto result = commandResponse->getCommandReply().getOwned();
         return Shard::CommandResponse(boost::none,
                                       result,
-                                      commandResponse->getMetadata().getOwned(),
                                       getStatusFromCommandResult(result),
                                       getWriteConcernStatusFromCommandResult(result));
     } catch (const DBException& ex) {
diff --git a/src/mongo/s/client/shard.h b/src/mongo/s/client/shard.h
index ead66c59fa5..a90d1160c0f 100644
--- a/src/mongo/s/client/shard.h
+++ b/src/mongo/s/client/shard.h
@@ -56,12 +56,10 @@ public:
     struct CommandResponse {
         CommandResponse(boost::optional<HostAndPort> hostAndPort,
                         BSONObj response,
-                        BSONObj metadata,
                         Status commandStatus,
                         Status writeConcernStatus)
             : hostAndPort(std::move(hostAndPort)),
               response(std::move(response)),
-              metadata(std::move(metadata)),
               commandStatus(std::move(commandStatus)),
               writeConcernStatus(std::move(writeConcernStatus)) {}
 
@@ -79,7 +77,6 @@ public:
 
         boost::optional<HostAndPort> hostAndPort;
         BSONObj response;
-        BSONObj metadata;
         Status commandStatus;
         Status writeConcernStatus;
     };
diff --git a/src/mongo/s/client/shard_remote.cpp b/src/mongo/s/client/shard_remote.cpp
index e6a67f8b83c..e8ea73f9225 100644
--- a/src/mongo/s/client/shard_remote.cpp
+++ b/src/mongo/s/client/shard_remote.cpp
@@ -244,7 +244,6 @@ StatusWith<Shard::CommandResponse> ShardRemote::_runCommand(OperationContext* op
 
     return Shard::CommandResponse(std::move(host),
                                   std::move(result),
-                                  response.metadata.getOwned(),
                                   std::move(commandStatus),
                                   std::move(writeConcernStatus));
 }
diff --git a/src/mongo/s/client/shard_remote_test.cpp b/src/mongo/s/client/shard_remote_test.cpp
index fe53c03dcc4..9503ecdc5d9 100644
--- a/src/mongo/s/client/shard_remote_test.cpp
+++ b/src/mongo/s/client/shard_remote_test.cpp
@@ -184,10 +184,11 @@ TEST_F(ShardRemoteTest, ScatterGatherRepliesWithLastCommittedOpTime) {
         onCommandWithMetadata([&](const executor::RemoteCommandRequest& request) {
             std::vector<BSONObj> batch = {BSON("_id" << 1)};
             CursorResponse cursorResponse(nss, CursorId(123), batch);
-            auto result = cursorResponse.toBSON(CursorResponse::ResponseType::InitialResponse);
+            auto result = BSONObjBuilder(
+                cursorResponse.toBSON(CursorResponse::ResponseType::InitialResponse));
+            result.appendElements(makeLastCommittedOpTimeMetadata(expectedTime));
 
-            return executor::RemoteCommandResponse(
-                result, makeLastCommittedOpTimeMetadata(expectedTime), Milliseconds(1));
+            return executor::RemoteCommandResponse(result.obj(), Milliseconds(1));
         });
     }
 
diff --git a/src/mongo/s/cluster_last_error_info_test.cpp b/src/mongo/s/cluster_last_error_info_test.cpp
index b9903192581..1de77def4b9 100644
--- a/src/mongo/s/cluster_last_error_info_test.cpp
+++ b/src/mongo/s/cluster_last_error_info_test.cpp
@@ -84,11 +84,10 @@ TEST_F(ClusterGetLastErrorTest,
     // Make the reply contain ShardingMetadata.
     repl::OpTime opTime{Timestamp{10, 10}, 10};
     onCommandWithMetadata([&](const RemoteCommandRequest& request) {
-        BSONObjBuilder metadataBob;
-        rpc::ShardingMetadata(opTime, OID() /* ignored OID field */)
-            .writeToMetadata(&metadataBob)
-            .transitional_ignore();
-        return RemoteCommandResponse(BSON("ok" << 1), metadataBob.obj(), Milliseconds(1));
+        auto bob = BSONObjBuilder(BSON("ok" << 1));
+        uassertStatusOK(
+            rpc::ShardingMetadata(opTime, OID() /* ignored OID field */).writeToMetadata(&bob));
+        return RemoteCommandResponse(bob.obj(), Milliseconds(1));
     });
 
     future.timed_get(kFutureTimeout);
@@ -129,11 +128,10 @@ TEST_F(ClusterGetLastErrorTest, ClusterLastErrorInfoNotUpdatedIfNotInitialized)
     // Make the reply contain ShardingMetadata.
     repl::OpTime opTime{Timestamp{10, 10}, 10};
     onCommandWithMetadata([&](const RemoteCommandRequest& request) {
-        BSONObjBuilder metadataBob;
-        rpc::ShardingMetadata(opTime, OID() /* ignored OID field */)
-            .writeToMetadata(&metadataBob)
-            .transitional_ignore();
-        return RemoteCommandResponse(BSON("ok" << 1), metadataBob.obj(), Milliseconds(1));
+        auto bob = BSONObjBuilder(BSON("ok" << 1));
+        uassertStatusOK(
+            rpc::ShardingMetadata(opTime, OID() /* ignored OID field */).writeToMetadata(&bob));
+        return RemoteCommandResponse(bob.obj(), Milliseconds(1));
     });
 
     future.timed_get(kFutureTimeout);
@@ -174,7 +172,7 @@ TEST_F(ClusterGetLastErrorTest, ClusterLastErrorInfoNotUpdatedIfReplyDoesntHaveS
     // Do not return ShardingMetadata in the reply.
     repl::OpTime opTime{Timestamp{10, 10}, 10};
     onCommandWithMetadata([&](const RemoteCommandRequest& request) {
-        return RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(1));
+        return RemoteCommandResponse(BSON("ok" << 1), Milliseconds(1));
     });
 
     future.timed_get(kFutureTimeout);
diff --git a/src/mongo/s/commands/cluster_multicast.cpp b/src/mongo/s/commands/cluster_multicast.cpp
index d1fcd3cc729..4585a3f8e01 100644
--- a/src/mongo/s/commands/cluster_multicast.cpp
+++ b/src/mongo/s/commands/cluster_multicast.cpp
@@ -134,7 +134,6 @@ public:
 
                     if (CommandHelpers::appendCommandStatusNoThrow(subbob, response.status)) {
                         subbob.append("data", response.data);
-                        subbob.append("metadata", response.metadata);
                         if (response.elapsedMillis) {
                             subbob.append("elapsedMillis", response.elapsedMillis->count());
                         }
diff --git a/src/mongo/s/commands/strategy.cpp b/src/mongo/s/commands/strategy.cpp
index 83e8ca526ae..850a9a61537 100644
--- a/src/mongo/s/commands/strategy.cpp
+++ b/src/mongo/s/commands/strategy.cpp
@@ -580,7 +580,6 @@ DbResponse Strategy::clientCommand(OperationContext* opCtx, const Message& m) {
         return {};  // Don't reply.
     }
 
-    reply->setMetadata(BSONObj());  // mongos doesn't use metadata but the API requires this call.
     return DbResponse{reply->done()};
 }
 
diff --git a/src/mongo/s/query/async_results_merger_test.cpp b/src/mongo/s/query/async_results_merger_test.cpp
index 64428771bb0..7960d22f018 100644
--- a/src/mongo/s/query/async_results_merger_test.cpp
+++ b/src/mongo/s/query/async_results_merger_test.cpp
@@ -186,7 +186,7 @@ protected:
         for (const auto& obj : objs) {
             ASSERT_TRUE(net->hasReadyRequests());
             Milliseconds millis(0);
-            RemoteCommandResponse response(obj, BSONObj(), millis);
+            RemoteCommandResponse response(obj, millis);
             executor::TaskExecutor::ResponseStatus responseStatus(response);
             net->scheduleResponse(net->getNextReadyRequest(), net->now(), responseStatus);
         }
diff --git a/src/mongo/s/sharding_task_executor.cpp b/src/mongo/s/sharding_task_executor.cpp
index 5b007cc44ec..2e84102ecc8 100644
--- a/src/mongo/s/sharding_task_executor.cpp
+++ b/src/mongo/s/sharding_task_executor.cpp
@@ -208,8 +208,7 @@ StatusWith<TaskExecutor::CallbackHandle> ShardingTaskExecutor::scheduleRemoteCom
 
         // Update getLastError info for the client if we're tracking it.
         if (clusterGLE) {
-            auto swShardingMetadata =
-                rpc::ShardingMetadata::readFromMetadata(args.response.metadata);
+            auto swShardingMetadata = rpc::ShardingMetadata::readFromMetadata(args.response.data);
             if (swShardingMetadata.isOK()) {
                 auto shardingMetadata = std::move(swShardingMetadata.getValue());
 
@@ -224,7 +223,7 @@ StatusWith<TaskExecutor::CallbackHandle> ShardingTaskExecutor::scheduleRemoteCom
             } else if (swShardingMetadata.getStatus() != ErrorCodes::NoSuchKey) {
                 warning() << "Got invalid sharding metadata "
                           << redact(swShardingMetadata.getStatus()) << " metadata object was '"
-                          << redact(args.response.metadata) << "'";
+                          << redact(args.response.data) << "'";
             }
         }
     };
diff --git a/src/mongo/scripting/mozjs/mongo.cpp b/src/mongo/scripting/mozjs/mongo.cpp
index 22a6a728461..0b88d21fb60 100644
--- a/src/mongo/scripting/mozjs/mongo.cpp
+++ b/src/mongo/scripting/mozjs/mongo.cpp
@@ -248,7 +248,6 @@ void MongoBase::Functions::runCommandWithMetadata::call(JSContext* cx, JS::CallA
 
     BSONObjBuilder mergedResultBob;
     mergedResultBob.append("commandReply", res->getCommandReply());
-    mergedResultBob.append("metadata", res->getMetadata());
 
     ValueReader(cx, args.rval()).fromBSON(mergedResultBob.obj(), nullptr, false);
     setHiddenMongo(cx, std::get<1>(resTuple), conn.get(), args);
diff --git a/src/mongo/tools/bridge.cpp b/src/mongo/tools/bridge.cpp
index 6938882953d..5793af94803 100644
--- a/src/mongo/tools/bridge.cpp
+++ b/src/mongo/tools/bridge.cpp
@@ -303,14 +303,12 @@ DbResponse ServiceEntryPointBridge::handleRequest(OperationContext* opCtx, const
         invariant(!isFireAndForgetCommand);
 
         auto replyBuilder = rpc::makeReplyBuilder(rpc::protocolForMessage(request));
-        BSONObj metadata;
         BSONObj reply;
         StatusWith<BSONObj> commandReply(reply);
         if (!status->isOK()) {
             commandReply = StatusWith<BSONObj>(*status);
         }
-        return {
-            replyBuilder->setCommandReply(std::move(commandReply)).setMetadata(metadata).done()};
+        return {replyBuilder->setCommandReply(std::move(commandReply)).done()};
     }