move experimental to seperate config/ff value

Author: tonytrg

cmd/github-mcp-server/main.go

@@ -83,6 +83,7 @@ var (
 				LogFilePath:          viper.GetString("log-file"),
 				ContentWindowSize:    viper.GetInt("content-window-size"),
 				LockdownMode:         viper.GetBool("lockdown-mode"),
+				Experimental:         viper.GetBool("experimental"),
 				RepoAccessCacheTTL:   &ttl,
 			}
 			return ghmcp.RunStdioServer(stdioServerConfig)
@@ -108,6 +109,7 @@ func init() {
 	rootCmd.PersistentFlags().String("gh-host", "", "Specify the GitHub hostname (for GitHub Enterprise etc.)")
 	rootCmd.PersistentFlags().Int("content-window-size", 5000, "Specify the content window size")
 	rootCmd.PersistentFlags().Bool("lockdown-mode", false, "Enable lockdown mode")
+	rootCmd.PersistentFlags().Bool("experimental", false, "Enable experimental features")
 	rootCmd.PersistentFlags().Duration("repo-access-cache-ttl", 5*time.Minute, "Override the repo access cache TTL (e.g. 1m, 0s to disable)")
 
 	// Bind flag to viper
@@ -122,6 +124,7 @@ func init() {
 	_ = viper.BindPFlag("host", rootCmd.PersistentFlags().Lookup("gh-host"))
 	_ = viper.BindPFlag("content-window-size", rootCmd.PersistentFlags().Lookup("content-window-size"))
 	_ = viper.BindPFlag("lockdown-mode", rootCmd.PersistentFlags().Lookup("lockdown-mode"))
+	_ = viper.BindPFlag("experimental", rootCmd.PersistentFlags().Lookup("experimental"))
 	_ = viper.BindPFlag("repo-access-cache-ttl", rootCmd.PersistentFlags().Lookup("repo-access-cache-ttl"))
 
 	// Add subcommands

internal/ghmcp/server.go

@@ -64,6 +64,9 @@ type MCPServerConfig struct {
 	// LockdownMode indicates if we should enable lockdown mode
 	LockdownMode bool
 
+	// Experimental indicates if we should enable experimental features
+	Experimental bool
+
 	// Logger is used for logging within the server
 	Logger *slog.Logger
 	// RepoAccessTTL overrides the default TTL for repository access cache entries.
@@ -208,7 +211,10 @@ func NewMCPServer(cfg MCPServerConfig) (*mcp.Server, error) {
 		clients.raw,
 		clients.repoAccess,
 		cfg.Translator,
-		github.FeatureFlags{LockdownMode: cfg.LockdownMode},
+		github.FeatureFlags{
+			LockdownMode: cfg.LockdownMode,
+			Experimental: cfg.Experimental,
+		},
 		cfg.ContentWindowSize,
 		featureChecker,
 	)
@@ -326,6 +332,9 @@ type StdioServerConfig struct {
 	// LockdownMode indicates if we should enable lockdown mode
 	LockdownMode bool
 
+	// Experimental indicates if we should enable experimental features
+	Experimental bool
+
 	// RepoAccessCacheTTL overrides the default TTL for repository access cache entries.
 	RepoAccessCacheTTL *time.Duration
 }
@@ -382,6 +391,7 @@ func RunStdioServer(cfg StdioServerConfig) error {
 		Translator:        t,
 		ContentWindowSize: cfg.ContentWindowSize,
 		LockdownMode:      cfg.LockdownMode,
+		Experimental:      cfg.Experimental,
 		Logger:            logger,
 		RepoAccessTTL:     cfg.RepoAccessCacheTTL,
 		TokenScopes:       tokenScopes,

pkg/github/feature_flags.go

@@ -3,8 +3,5 @@ package github
 // FeatureFlags defines runtime feature toggles that adjust tool behavior.
 type FeatureFlags struct {
 	LockdownMode bool
+	Experimental bool
 }
-
-// RemoteMCPExperimental is a long-lived feature flag for experimental remote MCP features.
-// This flag enables experimental behaviors in tools that are being tested for remote server deployment.
-const RemoteMCPExperimental = "remote_mcp_experimental"

pkg/github/hello_test.go pkg/github/feature_flags_test.gopkg/github/hello_test.go renamed to pkg/github/feature_flags_test.go

@@ -1,22 +1,87 @@
-package github_test
+package github
 
 import (
 	"context"
 	"encoding/json"
 	"testing"
 
-	"github.com/github/github-mcp-server/pkg/github"
 	"github.com/github/github-mcp-server/pkg/translations"
 	"github.com/modelcontextprotocol/go-sdk/mcp"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+
+	"github.com/github/github-mcp-server/pkg/inventory"
+	"github.com/github/github-mcp-server/pkg/scopes"
+	"github.com/github/github-mcp-server/pkg/utils"
+	"github.com/google/jsonschema-go/jsonschema"
 )
 
+// RemoteMCPExperimental is a long-lived feature flag for experimental remote MCP features.
+// This flag enables experimental behaviors in tools that are being tested for remote server deployment.
+const RemoteMCPEnthusiasticGreeting = "remote_mcp_enthusiastic_greeting"
+
+// HelloWorld returns a simple greeting tool that demonstrates feature flag conditional behavior.
+// This tool is for testing and demonstration purposes only.
+func HelloWorld(t translations.TranslationHelperFunc) inventory.ServerTool {
+	return NewTool(
+		ToolsetMetadataContext, // Use existing "context" toolset
+		mcp.Tool{
+			Name:        "hello_world",
+			Description: t("TOOL_HELLO_WORLD_DESCRIPTION", "A simple greeting tool that demonstrates feature flag conditional behavior"),
+			Annotations: &mcp.ToolAnnotations{
+				Title:        t("TOOL_HELLO_WORLD_TITLE", "Hello World"),
+				ReadOnlyHint: true,
+			},
+			InputSchema: &jsonschema.Schema{
+				Type: "object",
+				Properties: map[string]*jsonschema.Schema{
+					"name": {
+						Type:        "string",
+						Description: "Name to greet (optional, defaults to 'World')",
+					},
+				},
+			},
+		},
+		[]scopes.Scope{},
+		func(ctx context.Context, deps ToolDependencies, _ *mcp.CallToolRequest, args map[string]any) (*mcp.CallToolResult, any, error) {
+			// Extract name parameter (optional)
+			name := "World"
+			if nameArg, ok := args["name"].(string); ok && nameArg != "" {
+				name = nameArg
+			}
+
+			// Check feature flag to determine greeting style
+			var greeting string
+			if deps.IsFeatureEnabled(ctx, RemoteMCPEnthusiasticGreeting) {
+				// Experimental: More enthusiastic greeting
+				greeting = "🚀 Hello, " + name + "! Welcome to the EXPERIMENTAL future of MCP! 🎉"
+			} else {
+				// Default: Simple greeting
+				greeting = "Hello, " + name + "!"
+			}
+
+			// Build response
+			response := map[string]any{
+				"greeting":          greeting,
+				"experimental_mode": deps.IsFeatureEnabled(ctx, RemoteMCPEnthusiasticGreeting),
+				"timestamp":         "2026-01-12", // Static for demonstration
+			}
+
+			jsonBytes, err := json.Marshal(response)
+			if err != nil {
+				return utils.NewToolResultError("failed to marshal response"), nil, nil
+			}
+
+			return utils.NewToolResultText(string(jsonBytes)), nil, nil
+		},
+	)
+}
+
 func TestHelloWorld_ToolDefinition(t *testing.T) {
 	t.Parallel()
 
 	// Create tool
-	tool := github.HelloWorld(translations.NullTranslationHelper)
+	tool := HelloWorld(translations.NullTranslationHelper)
 
 	// Verify tool definition
 	assert.Equal(t, "hello_world", tool.Tool.Name)
@@ -68,23 +133,23 @@ func TestHelloWorld_ConditionalBehavior(t *testing.T) {
 
 			// Create feature checker based on test case
 			checker := func(_ context.Context, flagName string) (bool, error) {
-				if flagName == github.RemoteMCPExperimental {
+				if flagName == RemoteMCPEnthusiasticGreeting {
 					return tt.featureFlagEnabled, nil
 				}
 				return false, nil
 			}
 
 			// Create deps with the checker
-			deps := github.NewBaseDeps(
+			deps := NewBaseDeps(
 				nil, nil, nil, nil,
 				translations.NullTranslationHelper,
-				github.FeatureFlags{},
+				FeatureFlags{},
 				0,
 				checker,
 			)
 
 			// Get the tool and its handler
-			tool := github.HelloWorld(translations.NullTranslationHelper)
+			tool := HelloWorld(translations.NullTranslationHelper)
 			handler := tool.Handler(deps)
 
 			// Create request
@@ -102,7 +167,7 @@ func TestHelloWorld_ConditionalBehavior(t *testing.T) {
 			}
 
 			// Call the handler with deps in context
-			ctx := github.ContextWithDeps(context.Background(), deps)
+			ctx := ContextWithDeps(context.Background(), deps)
 			result, err := handler(ctx, &request)
 			require.NoError(t, err)
 			require.NotNil(t, result)

pkg/github/hello.go

@@ -84,6 +84,7 @@ func stubRepoAccessCache(client *githubv4.Client, ttl time.Duration) *lockdown.R
 func stubFeatureFlags(enabledFlags map[string]bool) FeatureFlags {
 	return FeatureFlags{
 		LockdownMode: enabledFlags["lockdown-mode"],
+		Experimental: enabledFlags["experimental"],
 	}
 }