diff --git a/handler/graphql.go b/handler/graphql.go
index c266d4c946c..8c3882ce9c2 100644
--- a/handler/graphql.go
+++ b/handler/graphql.go
@@ -30,7 +30,7 @@ type params struct {
 	Variables     map[string]interface{} `json:"variables"`
 }
 
-type websocketInitFunc func(ctx context.Context, initPayload InitPayload) bool
+type websocketInitFunc func(ctx context.Context, initPayload InitPayload) error
 
 type Config struct {
 	cacheSize                       int
@@ -255,7 +255,7 @@ func (tw *tracerWrapper) EndOperationExecution(ctx context.Context) {
 
 // WebsocketInitFunc is called when the server receives connection init message from the client.
 // This can be used to check initial payload to see whether to accept the websocket connection.
-func WebsocketInitFunc(websocketInitFunc func(ctx context.Context, initPayload InitPayload) bool) Option {
+func WebsocketInitFunc(websocketInitFunc func(ctx context.Context, initPayload InitPayload) error) Option {
 	return func(cfg *Config) {
 		cfg.websocketInitFunc = websocketInitFunc
 	}
diff --git a/handler/websocket.go b/handler/websocket.go
index a9a74893d20..07a1a8c2dd8 100644
--- a/handler/websocket.go
+++ b/handler/websocket.go
@@ -95,8 +95,8 @@ func (c *wsConnection) init() bool {
 		}
 
 		if c.cfg.websocketInitFunc != nil {
-			if ok := c.cfg.websocketInitFunc(c.ctx, c.initPayload); !ok {
-				c.sendConnectionError("invalid init payload")
+			if err := c.cfg.websocketInitFunc(c.ctx, c.initPayload); err != nil {
+				c.sendConnectionError(err.Error())
 				c.close(websocket.CloseNormalClosure, "terminated")
 				return false
 			}
diff --git a/handler/websocket_test.go b/handler/websocket_test.go
index b7d5e89905a..dc3e656e5fe 100644
--- a/handler/websocket_test.go
+++ b/handler/websocket_test.go
@@ -3,6 +3,7 @@ package handler
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"net/http/httptest"
 	"strings"
 	"testing"
@@ -176,8 +177,8 @@ func TestWebsocketInitFunc(t *testing.T) {
 	})
 
 	t.Run("accept connection if WebsocketInitFunc is provided and is accepting connection", func(t *testing.T) {
-		h := GraphQL(&executableSchemaStub{next}, WebsocketInitFunc(func(ctx context.Context, initPayload InitPayload) bool {
-			return true
+		h := GraphQL(&executableSchemaStub{next}, WebsocketInitFunc(func(ctx context.Context, initPayload InitPayload) error {
+			return nil
 		}))
 		srv := httptest.NewServer(h)
 		defer srv.Close()
@@ -191,8 +192,8 @@ func TestWebsocketInitFunc(t *testing.T) {
 	})
 
 	t.Run("reject connection if WebsocketInitFunc is provided and is accepting connection", func(t *testing.T) {
-		h := GraphQL(&executableSchemaStub{next}, WebsocketInitFunc(func(ctx context.Context, initPayload InitPayload) bool {
-			return false
+		h := GraphQL(&executableSchemaStub{next}, WebsocketInitFunc(func(ctx context.Context, initPayload InitPayload) error {
+			return errors.New("invalid init payload")
 		}))
 		srv := httptest.NewServer(h)
 		defer srv.Close()