diff --git a/main/src/main/scala/sbt/internal/server/NetworkChannel.scala b/main/src/main/scala/sbt/internal/server/NetworkChannel.scala
index 254ab3b2b..8f647f98d 100644
--- a/main/src/main/scala/sbt/internal/server/NetworkChannel.scala
+++ b/main/src/main/scala/sbt/internal/server/NetworkChannel.scala
@@ -22,18 +22,17 @@ import java.util.concurrent.atomic.{ AtomicBoolean, AtomicReference }
 
 import sbt.BasicCommandStrings.{ Shutdown, TerminateAction }
 import sbt.internal.langserver.{ CancelRequestParams, ErrorCodes, LogMessageParams, MessageType }
-import sbt.internal.langserver.{ CancelRequestParams, ErrorCodes }
 import sbt.internal.protocol.{
   JsonRpcNotificationMessage,
   JsonRpcRequestMessage,
   JsonRpcResponseError,
   JsonRpcResponseMessage
 }
+
 import sbt.internal.ui.{ UITask, UserThread }
 import sbt.internal.util.{ Prompt, ReadJsonFromInputStream, Terminal, Util }
 import sbt.internal.util.Terminal.TerminalImpl
 import sbt.internal.util.complete.{ Parser, Parsers }
-import sbt.protocol._
 import sbt.util.Logger
 
 import scala.annotation.{ nowarn, tailrec }
@@ -41,13 +40,14 @@ import scala.collection.mutable
 import scala.concurrent.duration._
 import scala.util.Try
 import scala.util.control.NonFatal
-import Serialization.{ attach, cancelReadSystemIn, readSystemIn }
+import sbt.protocol._
+import sbt.protocol.Serialization.{ attach, cancelReadSystemIn, readSystemIn, promptChannel }
+
+import sbt.protocol.codec.JsonProtocol._
 
 import sjsonnew._
 import sjsonnew.support.scalajson.unsafe.{ CompactPrinter, Converter }
 
-import BasicJsonProtocol._
-import Serialization.{ attach, promptChannel }
 import sbt.internal.util.ProgressState
 
 final class NetworkChannel(
@@ -259,7 +259,11 @@ final class NetworkChannel(
       case Some(request) =>
         pendingRequests -= request.id
         jsonRpcRespondError(request.id, err)
-      case _ => logMessage("error", s"Error ${err.code}: ${err.message}")
+      case _ =>
+        import sbt.internal.protocol.codec.JsonRPCProtocol._
+        val msg =
+          s"unmatched json error for requestId $execId: ${CompactPrinter(Converter.toJsonUnsafe(err))}"
+        log.debug(msg)
     }
   }
 
@@ -402,7 +406,6 @@ final class NetworkChannel(
 
   protected def onSettingQuery(execId: Option[String], req: SettingQuery) = {
     if (initialized) {
-      import sbt.protocol.codec.JsonProtocol._
       StandardMain.exchange.withState { s =>
         val structure = Project.extract(s).structure
         sbt.internal.server.SettingQuery.handleSettingQueryEither(req, structure) match {
@@ -420,7 +423,6 @@ final class NetworkChannel(
     if (initialized) {
       try {
         StandardMain.exchange.withState { sstate =>
-          import sbt.protocol.codec.JsonProtocol._
           def completionItems(s: State) = {
             Parser
               .completions(s.combinedParser, cp.query, cp.level.getOrElse(9))
@@ -515,7 +517,6 @@ final class NetworkChannel(
                 StandardMain.exchange.currentExec.exists(_.source.exists(_.channelName == name)))) {
               runningEngine.cancelAndShutdown()
 
-              import sbt.protocol.codec.JsonProtocol._
               respondResult(
                 ExecStatusEvent(
                   "Task cancelled",
@@ -806,7 +807,6 @@ final class NetworkChannel(
     ): Option[T] = {
       if (closed.get) None
       else {
-        import sbt.protocol.codec.JsonProtocol._
         val queue = VirtualTerminal.sendTerminalCapabilitiesQuery(name, jsonRpcRequest, query)
         Some(result(queue.take))
       }
@@ -833,7 +833,6 @@ final class NetworkChannel(
     override private[sbt] def getAttributes: Map[String, String] =
       if (closed.get) Map.empty
       else {
-        import sbt.protocol.codec.JsonProtocol._
         val queue = VirtualTerminal.sendTerminalAttributesQuery(
           name,
           jsonRpcRequest
@@ -851,7 +850,6 @@ final class NetworkChannel(
       }
     override private[sbt] def setAttributes(attributes: Map[String, String]): Unit =
       if (!closed.get) {
-        import sbt.protocol.codec.JsonProtocol._
         val attrs = TerminalSetAttributesCommand(
           iflag = attributes.getOrElse("iflag", ""),
           oflag = attributes.getOrElse("oflag", ""),
@@ -865,7 +863,6 @@ final class NetworkChannel(
       }
     override private[sbt] def getSizeImpl: (Int, Int) =
       if (!closed.get) {
-        import sbt.protocol.codec.JsonProtocol._
         val queue = VirtualTerminal.getTerminalSize(name, jsonRpcRequest)
         val res = try queue.take
         catch { case _: InterruptedException => TerminalGetSizeResponse(1, 1) }
@@ -873,7 +870,6 @@ final class NetworkChannel(
       } else (1, 1)
     override def setSize(width: Int, height: Int): Unit =
       if (!closed.get) {
-        import sbt.protocol.codec.JsonProtocol._
         val size = TerminalSetSizeCommand(width, height)
         val queue = VirtualTerminal.setTerminalSize(name, jsonRpcRequest, size)
         try queue.take
@@ -881,7 +877,6 @@ final class NetworkChannel(
       }
     private[this] def setRawMode(toggle: Boolean): Unit = {
       if (!closed.get || false) {
-        import sbt.protocol.codec.JsonProtocol._
         val raw = TerminalSetRawModeCommand(toggle)
         val queue = VirtualTerminal.setTerminalRawMode(name, jsonRpcRequest, raw)
         try queue.take
@@ -892,7 +887,6 @@ final class NetworkChannel(
     override private[sbt] def exitRawMode(): Unit = setRawMode(false)
     override def setEchoEnabled(toggle: Boolean): Unit =
       if (!closed.get) {
-        import sbt.protocol.codec.JsonProtocol._
         val echo = TerminalSetEchoCommand(toggle)
         val queue = VirtualTerminal.setTerminalEcho(name, jsonRpcRequest, echo)
         try queue.take