fix: make Eino exit and transfer work on AgenticMessage state

Official ExitTool still writes classic Message react state, which breaks supervisor delivery on the Agentic path.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/multiagent/eino_agentic_react_state.go

@@ -0,0 +1,70 @@
+package multiagent
+
+import (
+	"context"
+	"fmt"
+	"reflect"
+
+	"github.com/cloudwego/eino/adk"
+	"github.com/cloudwego/eino/compose"
+)
+
+// mutateADKReactState updates ChatModelAgent react state regardless of whether
+// the live graph stores typedState[*schema.Message] or typedState[*schema.AgenticMessage].
+// Eino v0.9.14 only exports SendToolGenAction against the classic Message state.
+func mutateADKReactState(ctx context.Context, mutate func(st reflect.Value) error) error {
+	if mutate == nil {
+		return fmt.Errorf("adk react state mutate is nil")
+	}
+	return compose.ProcessState(ctx, func(_ context.Context, st any) error {
+		if st == nil {
+			return fmt.Errorf("adk react state is nil")
+		}
+		v := reflect.ValueOf(st)
+		if v.Kind() != reflect.Pointer || v.IsNil() {
+			return fmt.Errorf("unexpected adk react state type %T", st)
+		}
+		return mutate(v.Elem())
+	})
+}
+
+func sendADKToolGenAction(ctx context.Context, toolName string, action *adk.AgentAction) error {
+	if action == nil {
+		return fmt.Errorf("adk tool gen action is nil")
+	}
+	key := toolName
+	if toolCallID := compose.GetToolCallID(ctx); toolCallID != "" {
+		key = toolCallID
+	}
+	return mutateADKReactState(ctx, func(st reflect.Value) error {
+		field := st.FieldByName("ToolGenActions")
+		if !field.IsValid() || field.Kind() != reflect.Map {
+			return fmt.Errorf("adk react state missing ToolGenActions")
+		}
+		if !field.CanSet() {
+			return fmt.Errorf("cannot set ToolGenActions on adk react state")
+		}
+		if field.IsNil() {
+			field.Set(reflect.MakeMap(field.Type()))
+		}
+		field.SetMapIndex(reflect.ValueOf(key), reflect.ValueOf(action))
+		return nil
+	})
+}
+
+func clearADKReturnDirectly(ctx context.Context) error {
+	return mutateADKReactState(ctx, func(st reflect.Value) error {
+		zeroExportedField(st, "ReturnDirectlyToolCallID")
+		zeroExportedField(st, "HasReturnDirectly")
+		zeroExportedField(st, "ReturnDirectlyEvent")
+		return nil
+	})
+}
+
+func zeroExportedField(st reflect.Value, name string) {
+	field := st.FieldByName(name)
+	if !field.IsValid() || !field.CanSet() {
+		return
+	}
+	field.Set(reflect.Zero(field.Type()))
+}