diff --git a/pkg/flags/setoas.go b/pkg/flags/setoas.go
new file mode 100644
index 0000000..72b4007
--- /dev/null
+++ b/pkg/flags/setoas.go
@@ -0,0 +1,70 @@
+//  Copyright 2024 Google LLC
+//
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the License.
+//  You may obtain a copy of the License at
+//
+//       http://www.apache.org/licenses/LICENSE-2.0
+//
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS,
+//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//  See the License for the specific language governing permissions and
+//  limitations under the License.
+
+package flags
+
+import (
+	"fmt"
+	"github.com/go-errors/errors"
+	"github.com/micovery/apigee-yaml-toolkit/pkg/parser"
+	"github.com/micovery/apigee-yaml-toolkit/pkg/values"
+	"gopkg.in/yaml.v3"
+	"os"
+	"strings"
+)
+
+type SetOAS struct {
+	Data *values.Map
+}
+
+func NewSetOAS(data *values.Map) SetOAS {
+	return SetOAS{Data: data}
+}
+
+func (v *SetOAS) String() string {
+	return fmt.Sprintf("%v", v.Data)
+}
+
+func (v *SetOAS) Set(entry string) error {
+	key, filePath, found := strings.Cut(entry, "=")
+	if !found {
+		return errors.Errorf("missing file path in set-oas for key=%s", key)
+	}
+
+	specFileMap := make(map[string]any)
+	specFileText, err := os.ReadFile(filePath)
+	if err != nil {
+		return errors.New(err)
+	}
+
+	err = yaml.Unmarshal(specFileText, specFileMap)
+	if err != nil {
+		return errors.New(err)
+	}
+
+	oas, err := parser.ParseOAS(filePath)
+	if err != nil {
+		return errors.New(err)
+	}
+	specVersion := oas.GetSpecInfo().VersionNumeric
+
+	if !(specVersion == 2.0 || specVersion >= 3.0) {
+		return errors.Errorf(`OAS version "%v" is not supported`, specVersion)
+	}
+
+	v.Data.Set(key, specFileMap)
+	v.Data.Set(fmt.Sprintf("%s_string", key), string(specFileText))
+
+	return nil
+}