resolve gemini coments

## Description

> Should include a concise description of the changes (bug or feature),
it's
> impact, along with a summary of the solution

## PR Checklist

> Thank you for opening a Pull Request! Before submitting your PR, there
are a
> few things you can do to make sure it goes smoothly:

- [ ] Make sure you reviewed

[CONTRIBUTING.md](https://github.com/googleapis/genai-toolbox/blob/main/CONTRIBUTING.md)
- [ ] Make sure to open an issue as a

[bug/issue](https://github.com/googleapis/genai-toolbox/issues/new/choose)
  before writing your code! That way we can discuss the change, evaluate
  designs, and agree on the general idea
- [ ] Ensure the tests and linter pass
- [ ] Code coverage does not decrease (if any source code was changed)
- [ ] Appropriate docs were updated (if necessary)
- [ ] Make sure to add `!` if this involve a breaking change

🛠️ Fixes #<issue_number_goes_here>

cmd/root.go

@@ -125,6 +125,7 @@ func NewCommand(opts *internal.ToolboxOptions) *cobra.Command {
 	// TODO: Insecure by default. Might consider updating this for v1.0.0
 	flags.StringSliceVar(&opts.Cfg.AllowedOrigins, "allowed-origins", []string{"*"}, "Specifies a list of origins permitted to access this server. Defaults to '*'.")
 	flags.StringSliceVar(&opts.Cfg.AllowedHosts, "allowed-hosts", []string{"*"}, "Specifies a list of hosts permitted to access this server. Defaults to '*'.")
+	flags.IntVar(&opts.Cfg.PollInterval, "poll-interval", 0, "Specifies the polling frequency (seconds) for configuration file updates.")
 
 	// wrap RunE command so that we have access to original Command object
 	cmd.RunE = func(*cobra.Command, []string) error { return run(cmd, opts) }
@@ -195,8 +196,22 @@ func validateReloadEdits(
 	return sourcesMap, authServicesMap, embeddingModelsMap, toolsMap, toolsetsMap, promptsMap, promptsetsMap, nil
 }
 
+// Helper to check if a file has a newer ModTime than stored in the map
+func checkModTime(path string, lastSeen map[string]time.Time) bool {
+	info, err := os.Stat(path)
+	if err != nil {
+		return false
+	}
+	mTime := info.ModTime()
+	if mTime.After(lastSeen[path]) {
+		lastSeen[path] = mTime
+		return true
+	}
+	return false
+}
+
 // watchChanges checks for changes in the provided yaml tools file(s) or folder.
-func watchChanges(ctx context.Context, watchDirs map[string]bool, watchedFiles map[string]bool, s *server.Server) {
+func watchChanges(ctx context.Context, watchDirs map[string]bool, watchedFiles map[string]bool, s *server.Server, pollTickerSecond int) {
 	logger, err := util.LoggerFromContext(ctx)
 	if err != nil {
 		panic(err)
@@ -238,6 +253,42 @@ func watchChanges(ctx context.Context, watchDirs map[string]bool, watchedFiles m
 		logger.DebugContext(ctx, fmt.Sprintf("Added directory %s to watcher.", dir))
 	}
 
+	lastSeen := make(map[string]time.Time)
+	var pollTickerChan <-chan time.Time
+	if pollTickerSecond > 0 {
+		ticker := time.NewTicker(time.Duration(pollTickerSecond) * time.Second)
+		defer ticker.Stop()
+		pollTickerChan = ticker.C // Assign the channel
+		logger.DebugContext(ctx, fmt.Sprintf("NFS polling enabled every %v", pollTickerSecond))
+
+		// Pre-populate lastSeen to avoid an initial spurious reload
+		if watchingFolder {
+			files, err := os.ReadDir(folderToWatch)
+			if err != nil {
+				logger.WarnContext(ctx, "error reading tools folder on initial scan %s", err)
+			} else {
+				for _, f := range files {
+					if !f.IsDir() && (strings.HasSuffix(f.Name(), ".yaml") || strings.HasSuffix(f.Name(), ".yml")) {
+						fullPath := filepath.Join(folderToWatch, f.Name())
+						info, err := os.Stat(fullPath)
+						if err == nil {
+							lastSeen[fullPath] = info.ModTime()
+						}
+					}
+				}
+			}
+		} else {
+			for f := range watchedFiles {
+				info, err := os.Stat(f)
+				if err == nil {
+					lastSeen[f] = info.ModTime()
+				}
+			}
+		}
+	} else {
+		logger.DebugContext(ctx, "NFS polling disabled (interval is 0)")
+	}
+
 	// debounce timer is used to prevent multiple writes triggering multiple reloads
 	debounceDelay := 100 * time.Millisecond
 	debounce := time.NewTimer(1 * time.Minute)
@@ -248,6 +299,55 @@ func watchChanges(ctx context.Context, watchDirs map[string]bool, watchedFiles m
 		case <-ctx.Done():
 			logger.DebugContext(ctx, "file watcher context cancelled")
 			return
+		case <-pollTickerChan:
+			changed := false
+			currentDiskFiles := make(map[string]bool)
+			// Get files that are currently on disk
+			if watchingFolder {
+				files, err := os.ReadDir(folderToWatch)
+				if err != nil {
+					logger.WarnContext(ctx, "error reading tools folder %s", err)
+					continue
+				}
+				for _, f := range files {
+					if !f.IsDir() && (strings.HasSuffix(f.Name(), ".yaml") || strings.HasSuffix(f.Name(), ".yml")) {
+						fullPath := filepath.Join(folderToWatch, f.Name())
+						currentDiskFiles[fullPath] = true
+
+						if checkModTime(fullPath, lastSeen) {
+							changed = true
+						}
+					}
+				}
+			} else {
+				for f := range watchedFiles {
+					// We must explicitly check existence here because checkModTime
+					// swallows errors (returns false), making it impossible to
+					// distinguish between "no change" and "file deleted".
+					if _, err := os.Stat(f); err == nil {
+						currentDiskFiles[f] = true
+						if checkModTime(f, lastSeen) {
+							changed = true
+						}
+					}
+				}
+			}
+
+			// Check for Deletions
+			// If it was in lastSeen but is NOT in currentDiskFiles, it's
+			// deleted; we will need to reload the server.
+			for path := range lastSeen {
+				if !currentDiskFiles[path] {
+					logger.DebugContext(ctx, fmt.Sprintf("File deleted (detected via polling): %s", path))
+					delete(lastSeen, path)
+					changed = true
+				}
+			}
+			if changed {
+				logger.DebugContext(ctx, "NFS remote change detected via polling")
+				// once this timer runs out, it will trigger debounce.C
+				debounce.Reset(debounceDelay)
+			}
 		case err, ok := <-w.Errors:
 			if !ok {
 				logger.WarnContext(ctx, "file watcher was closed unexpectedly")
@@ -417,7 +517,7 @@ func run(cmd *cobra.Command, opts *internal.ToolboxOptions) error {
 	if isCustomConfigured && !opts.Cfg.DisableReload {
 		watchDirs, watchedFiles := resolveWatcherInputs(opts.ToolsFile, opts.ToolsFiles, opts.ToolsFolder)
 		// start watching the file(s) or folder for changes to trigger dynamic reloading
-		go watchChanges(ctx, watchDirs, watchedFiles, s)
+		go watchChanges(ctx, watchDirs, watchedFiles, s, opts.Cfg.PollInterval)
 	}
 
 	// wait for either the server to error out or the command's context to be canceled

cmd/root_test.go

@@ -590,7 +590,7 @@ func TestSingleEdit(t *testing.T) {
 	watchedFiles := map[string]bool{cleanFileToWatch: true}
 	watchDirs := map[string]bool{watchDir: true}
 
-	go watchChanges(ctx, watchDirs, watchedFiles, mockServer)
+	go watchChanges(ctx, watchDirs, watchedFiles, mockServer, 0)
 
 	// escape backslash so regex doesn't fail on windows filepaths
 	regexEscapedPathFile := strings.ReplaceAll(cleanFileToWatch, `\`, `\\\\*\\`)

docs/en/reference/cli.md

@@ -28,6 +28,7 @@ description: >
 |              | `--allowed-origins`        | Specifies a list of origins permitted to access this server for CORs access.                                                                                                     | `*`         |
 |              | `--allowed-hosts`          | Specifies a list of hosts permitted to access this server to prevent DNS rebinding attacks.                                                                                      | `*`         |
 |              | `--user-agent-metadata`    | Appends additional metadata to the User-Agent.                                                                                                                                   |             |
+|              | `--poll-interval`          | Specifies the polling frequency (seconds) for configuration file updates.                                                                                                        | `0`         |
 | `-v`         | `--version`                | version for toolbox                                                                                                                                                              |             |
 
 ## Sub Commands
@@ -136,6 +137,16 @@ used at a time.
 Toolbox enables dynamic reloading by default. To disable, use the
 `--disable-reload` flag.
 
+Use the `--poll-interval` flag to manually detect configuration file updates.
+When the poll interval is `0`, the polling system is disabled.
+
+{{< notice tip >}}
+For polling system to be effective when running Kubernetes, PersistentVolume or
+StorageClass must be set to refresh attributes rapidly by setting `actimeo=1`.
+Actimeo setting determines the duration for which a client trusts its local
+cache for file attributes.
+{{< /notice >}}
+
 ### Toolbox UI
 
 To launch Toolbox's interactive UI, use the `--ui` flag. This allows you to test

internal/server/config.go

@@ -75,6 +75,8 @@ type ServerConfig struct {
 	AllowedHosts []string
 	// UserAgentMetadata specifies additional metadata to append to the User-Agent string.
 	UserAgentMetadata []string
+	// PollInterval sets the polling frequency for configuration file updates.
+	PollInterval int
 }
 
 type logFormat string

tests/alloydbomni/alloydb_omni_integration_test.go

@@ -36,15 +36,17 @@ var (
 	AlloyDBDatabase = "postgres"
 )
 
-// Copied over from postgres.go
-func initPostgresConnectionPool(host, port, user, pass, dbname string) (*pgxpool.Pool, error) {
-	// urlExample := "postgres:dd//username:password@localhost:5432/database_name"
-	url := &url.URL{
+func buildPostgresURL(host, port, user, pass, dbname string) *url.URL {
+	return &url.URL{
 		Scheme: "postgres",
 		User:   url.UserPassword(user, pass),
 		Host:   fmt.Sprintf("%s:%s", host, port),
 		Path:   dbname,
 	}
+}
+
+func initPostgresConnectionPool(host, port, user, pass, dbname string) (*pgxpool.Pool, error) {
+	url := buildPostgresURL(host, port, user, pass, dbname)
 	pool, err := pgxpool.New(context.Background(), url.String())
 	if err != nil {
 		return nil, fmt.Errorf("Unable to create connection pool: %w", err)
@@ -63,7 +65,8 @@ func setupAlloyDBContainer(ctx context.Context, t *testing.T) (string, string, f
 			"POSTGRES_PASSWORD": AlloyDBPass,
 		},
 		WaitingFor: wait.ForAll(
-			wait.ForLog("Post Startup: Successfully reinstalled extensions"),
+			wait.ForLog("database system was shut down at"),
+			wait.ForLog("database system is ready to accept connections"),
 			wait.ForExposedPort(),
 		),
 	}