diff --git a/pkg/core/dao/dao_test.go b/pkg/core/dao/dao_test.go
index acc88c9ed..4ae08f4e1 100644
--- a/pkg/core/dao/dao_test.go
+++ b/pkg/core/dao/dao_test.go
@@ -197,7 +197,7 @@ func TestStoreAsTransaction(t *testing.T) {
 						stackitem.NewBool(false),
 					}),
 					ArgumentsCount: 1,
-					IsValid:        true,
+					Truncated:      false,
 				}},
 			},
 		}
diff --git a/pkg/core/interop/context.go b/pkg/core/interop/context.go
index 67f7718d7..08be26d20 100644
--- a/pkg/core/interop/context.go
+++ b/pkg/core/interop/context.go
@@ -71,6 +71,7 @@ type Context struct {
 	loadToken        func(ic *Context, id int32) error
 	GetRandomCounter uint32
 	signers          []transaction.Signer
+	SaveInvocations  bool
 }
 
 // NewContext returns new interop context.
@@ -81,20 +82,21 @@ func NewContext(trigger trigger.Type, bc Ledger, d *dao.Simple, baseExecFee, bas
 	dao := d.GetPrivate()
 	cfg := bc.GetConfig().ProtocolConfiguration
 	return &Context{
-		Chain:          bc,
-		Network:        uint32(cfg.Magic),
-		Hardforks:      cfg.Hardforks,
-		Natives:        natives,
-		Trigger:        trigger,
-		Block:          block,
-		Tx:             tx,
-		DAO:            dao,
-		Log:            log,
-		Invocations:    make(map[util.Uint160]int),
-		getContract:    getContract,
-		baseExecFee:    baseExecFee,
-		baseStorageFee: baseStorageFee,
-		loadToken:      loadTokenFunc,
+		Chain:           bc,
+		Network:         uint32(cfg.Magic),
+		Hardforks:       cfg.Hardforks,
+		Natives:         natives,
+		Trigger:         trigger,
+		Block:           block,
+		Tx:              tx,
+		DAO:             dao,
+		Log:             log,
+		Invocations:     make(map[util.Uint160]int),
+		getContract:     getContract,
+		baseExecFee:     baseExecFee,
+		baseStorageFee:  baseStorageFee,
+		loadToken:       loadTokenFunc,
+		SaveInvocations: bc.GetConfig().SaveInvocations,
 	}
 }
 
diff --git a/pkg/core/interop/contract/call.go b/pkg/core/interop/contract/call.go
index be1bbfdea..1cbabf5f3 100644
--- a/pkg/core/interop/contract/call.go
+++ b/pkg/core/interop/contract/call.go
@@ -70,23 +70,22 @@ func Call(ic *interop.Context) error {
 	}
 	hasReturn := md.ReturnType != smartcontract.VoidType
 
-	if ic.Chain.GetConfig().Ledger.SaveInvocations {
-		arr := stackitem.NewArray(args)
-		arrCount := len(args)
-		valid := true
-		argBytes := []byte{}
-		if argBytes, err = ic.DAO.GetItemCtx().Serialize(arr, false); err != nil {
-			arr = stackitem.NewArray([]stackitem.Item{})
-			valid = false
+	if ic.SaveInvocations {
+		var (
+			arrCount  = len(args)
+			truncated = false
+			argBytes  []byte
+		)
+		if argBytes, err = ic.DAO.GetItemCtx().Serialize(stackitem.NewArray(args), false); err != nil {
+			truncated = true
 		}
 
 		ic.InvocationCalls = append(ic.InvocationCalls, state.ContractInvocation{
 			Hash:           u,
 			Method:         method,
-			Arguments:      arr,
 			ArgumentsBytes: argBytes,
 			ArgumentsCount: uint32(arrCount),
-			IsValid:        valid,
+			Truncated:      truncated,
 		})
 	}
 	return callInternal(ic, cs, method, fs, hasReturn, args, true)
diff --git a/pkg/core/state/notification_event.go b/pkg/core/state/notification_event.go
index 0d0394a4d..72c1a8dc8 100644
--- a/pkg/core/state/notification_event.go
+++ b/pkg/core/state/notification_event.go
@@ -20,13 +20,16 @@ type NotificationEvent struct {
 	Item       *stackitem.Array `json:"state"`
 }
 
+// ContractInvocation contains method call information.
+// The Arguments field will be nil if serialization of the arguments exceeds a predefined limit
+// (for security reasons). In that case Truncated will be set to true.
 type ContractInvocation struct {
-	Hash           util.Uint160     `json:"contract_hash"`
+	Hash           util.Uint160     `json:"contracthash"`
 	Method         string           `json:"method"`
 	Arguments      *stackitem.Array `json:"arguments"`
-	ArgumentsBytes []byte           `json:"arguments_bytes"`
-	ArgumentsCount uint32           `json:"arguments_count"`
-	IsValid        bool             `json:"is_valid"`
+	ArgumentsBytes []byte
+	ArgumentsCount uint32 `json:"argumentscount"`
+	Truncated      bool   `json:"truncated"`
 }
 
 func (ci *ContractInvocation) DecodeBinary(r *io.BinReader) {
@@ -39,7 +42,7 @@ func (ci *ContractInvocation) DecodeBinary(r *io.BinReader) {
 	}
 	ci.Arguments = si.(*stackitem.Array)
 	ci.ArgumentsCount = r.ReadU32LE()
-	ci.IsValid = r.ReadBool()
+	ci.Truncated = r.ReadBool()
 }
 
 func (ci *ContractInvocation) EncodeBinaryWithContext(w *io.BinWriter, sc *stackitem.SerializationContext) {
@@ -47,7 +50,7 @@ func (ci *ContractInvocation) EncodeBinaryWithContext(w *io.BinWriter, sc *stack
 	w.WriteString(ci.Method)
 	w.WriteVarBytes(ci.ArgumentsBytes)
 	w.WriteU32LE(ci.ArgumentsCount)
-	w.WriteBool(ci.IsValid)
+	w.WriteBool(ci.Truncated)
 }
 
 // MarshalJSON implements the json.Marshaler interface.
@@ -61,7 +64,7 @@ func (ci ContractInvocation) MarshalJSON() ([]byte, error) {
 		Method:         ci.Method,
 		Arguments:      item,
 		ArgumentsCount: ci.ArgumentsCount,
-		IsValid:        ci.IsValid,
+		Truncated:      ci.Truncated,
 	})
 }
 
@@ -82,7 +85,7 @@ func (ci *ContractInvocation) UnmarshalJSON(data []byte) error {
 	ci.Method = aux.Method
 	ci.Hash = aux.Hash
 	ci.ArgumentsCount = aux.ArgumentsCount
-	ci.IsValid = aux.IsValid
+	ci.Truncated = aux.Truncated
 	return nil
 }
 
@@ -194,7 +197,9 @@ func (aer *AppExecResult) DecodeBinary(r *io.BinReader) {
 	aer.Stack = arr
 	r.ReadArray(&aer.Events)
 	aer.FaultException = r.ReadString()
-	r.ReadArray(&aer.Invocations)
+	if r.Len() > 0 {
+		r.ReadArray(&aer.Invocations)
+	}
 }
 
 // notificationEventAux is an auxiliary struct for NotificationEvent JSON marshalling.
@@ -288,11 +293,11 @@ type Execution struct {
 }
 
 type ContractInvocationAux struct {
-	Hash           util.Uint160    `json:"contract_hash"`
+	Hash           util.Uint160    `json:"contracthash"`
 	Method         string          `json:"method"`
 	Arguments      json.RawMessage `json:"arguments"`
-	ArgumentsCount uint32          `json:"arguments_count"`
-	IsValid        bool            `json:"is_valid"`
+	ArgumentsCount uint32          `json:"argumentscount"`
+	Truncated      bool            `json:"truncated"`
 }
 
 // executionAux represents an auxiliary struct for Execution JSON marshalling.