diff --git a/pkg/mcp/pftools/errors.go b/pkg/mcp/pftools/errors.go
index 62e23e6..149c83f 100644
--- a/pkg/mcp/pftools/errors.go
+++ b/pkg/mcp/pftools/errors.go
@@ -16,6 +16,8 @@ package pftools
 
 import (
 	"errors"
+	"net"
+	"net/url"
 	"strings"
 
 	"github.com/apache/pulsar-client-go/pulsaradmin/pkg/rest"
@@ -30,16 +32,99 @@ var (
 
 // IsClusterUnhealthy checks if an error indicates cluster health issues
 func IsClusterUnhealthy(err error) bool {
+	if err == nil {
+		return false
+	}
+
 	if restErr, ok := err.(rest.Error); ok {
-		return restErr.Code == 503 && strings.Contains(restErr.Reason, "no healthy upstream")
+		if restErr.Code == 503 && strings.Contains(strings.ToLower(restErr.Reason), "no healthy upstream") {
+			return true
+		}
 	}
-	return false
+
+	return IsNetworkError(err)
 }
 
 // IsAuthError reports whether the error is an authorization error.
 func IsAuthError(err error) bool {
+	if err == nil {
+		return false
+	}
+	if restErr, ok := err.(rest.Error); ok {
+		return restErr.Code == 401 || restErr.Code == 403
+	}
+	return isAuthErrorText(err.Error())
+}
+
+// IsNotFoundError reports whether the error is a not found error.
+func IsNotFoundError(err error) bool {
+	if err == nil {
+		return false
+	}
 	if restErr, ok := err.(rest.Error); ok {
-		return restErr.Code == 403
+		return restErr.Code == 404
+	}
+	return isNotFoundText(err.Error())
+}
+
+// IsNetworkError reports whether the error indicates a network failure.
+func IsNetworkError(err error) bool {
+	if err == nil {
+		return false
+	}
+	var netErr net.Error
+	if errors.As(err, &netErr) {
+		return true
+	}
+	var urlErr *url.Error
+	if errors.As(err, &urlErr) {
+		return true
+	}
+
+	errStr := strings.ToLower(err.Error())
+	networkErrorPatterns := []string{
+		"connection reset",
+		"connection refused",
+		"broken pipe",
+		"tls handshake timeout",
+		"i/o timeout",
+		"context deadline exceeded",
+		"timeout",
+		"eof",
+		"network is unreachable",
+		"no route to host",
+	}
+	for _, pattern := range networkErrorPatterns {
+		if strings.Contains(errStr, pattern) {
+			return true
+		}
+	}
+	return false
+}
+
+func isAuthErrorText(text string) bool {
+	lowered := strings.ToLower(text)
+	authErrorPatterns := []string{
+		"unauthorized",
+		"forbidden",
+		"token expired",
+		"expired token",
+		"invalid token",
+		"401",
+		"403",
+	}
+	for _, pattern := range authErrorPatterns {
+		if strings.Contains(lowered, pattern) {
+			return true
+		}
+	}
+	return false
+}
+
+func isNotFoundText(text string) bool {
+	lowered := strings.ToLower(text)
+	if strings.Contains(lowered, "404") && strings.Contains(lowered, "not found") {
+		return true
 	}
 	return false
 }
diff --git a/pkg/mcp/pftools/errors_test.go b/pkg/mcp/pftools/errors_test.go
new file mode 100644
index 0000000..cc5cee5
--- /dev/null
+++ b/pkg/mcp/pftools/errors_test.go
@@ -0,0 +1,63 @@
+package pftools
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/apache/pulsar-client-go/pulsaradmin/pkg/rest"
+)
+
+func TestIsClusterUnhealthy(t *testing.T) {
+	t.Run("no healthy upstream", func(t *testing.T) {
+		err := rest.Error{Code: 503, Reason: "no healthy upstream"}
+		if !IsClusterUnhealthy(err) {
+			t.Fatalf("expected cluster unhealthy for 503 no healthy upstream")
+		}
+	})
+
+	t.Run("network error text", func(t *testing.T) {
+		err := errors.New("read tcp 127.0.0.1:1234->127.0.0.1:443: read: connection reset by peer")
+		if !IsClusterUnhealthy(err) {
+			t.Fatalf("expected cluster unhealthy for network error text")
+		}
+	})
+
+	t.Run("non cluster error", func(t *testing.T) {
+		err := rest.Error{Code: 500, Reason: "internal error"}
+		if IsClusterUnhealthy(err) {
+			t.Fatalf("did not expect cluster unhealthy for 500 internal error")
+		}
+	})
+}
+
+func TestIsAuthError(t *testing.T) {
+	t.Run("rest auth error", func(t *testing.T) {
+		err := rest.Error{Code: 401, Reason: "unauthorized"}
+		if !IsAuthError(err) {
+			t.Fatalf("expected auth error for 401")
+		}
+	})
+
+	t.Run("text auth error", func(t *testing.T) {
+		err := errors.New("token expired")
+		if !IsAuthError(err) {
+			t.Fatalf("expected auth error for token expired")
+		}
+	})
+}
+
+func TestIsNotFoundError(t *testing.T) {
+	t.Run("rest not found", func(t *testing.T) {
+		err := rest.Error{Code: 404, Reason: "Not Found"}
+		if !IsNotFoundError(err) {
+			t.Fatalf("expected not found for 404")
+		}
+	})
+
+	t.Run("text not found", func(t *testing.T) {
+		err := errors.New("code: 404 reason: 404 Not Found")
+		if !IsNotFoundError(err) {
+			t.Fatalf("expected not found for 404 text")
+		}
+	})
+}
diff --git a/pkg/mcp/pftools/manager.go b/pkg/mcp/pftools/manager.go
index a509c75..e150319 100644
--- a/pkg/mcp/pftools/manager.go
+++ b/pkg/mcp/pftools/manager.go
@@ -157,7 +157,7 @@ func (m *PulsarFunctionManager) updateFunctions() {
 		log.Printf("Failed to get functions list: %v", err)
 
 		// Check if this is a cluster health error and invoke callback if configured
-		if (IsClusterUnhealthy(err) || IsAuthError(err)) && m.clusterErrorHandler != nil {
+		if (IsClusterUnhealthy(err) || IsAuthError(err) || IsNotFoundError(err)) && m.clusterErrorHandler != nil {
 			go m.clusterErrorHandler(m, err)
 		}
 		return