diff --git a/sandbox/controller.go b/sandbox/controller.go
index 925307829..e597e4b73 100644
--- a/sandbox/controller.go
+++ b/sandbox/controller.go
@@ -23,22 +23,8 @@ import (
 )
 
 // Controller is an interface to manage sandboxes at runtime.
-// When running the traditional containerd shim, the workflow looks as follows:
-// For each new task we're about to run:
-//  1. Invoke `shim_binary --start` to obtain `TaskService` address (printed in stdout)
-//  2. Call TaskService.RunContainer(id=1)
-//  3. Exec `shim_binary --delete` to stop shim
-//  4. Exec `shim_binary --start` again to obtain another `TaskService` address
-//  5. TaskService.RunContainer(id=2)
-//  6. Exec `shim_binary --delete` to stop shim
-//
-// When running in sandbox mode, shim must implement `SandboxService`.
-// In sandbox mode shim lifetimes are managed manually via sandbox API.
-//  1. Client calls `client.SandboxController.Start()` to launch new shim and create sandbox process
-//  2. Run containers with `shim.TaskService.RunContainer(id=1)` and another one `shim.TaskService.RunContainer(id=2)`
-//  3. ... usual container lifecycle calls to `shim.TaskService`
-//  4. Client calls shim to stop the sandbox with `client.SandboxService.Shutdown()`
-//  5. Shim implementation will perform cleanup similar to regular task service (e.g. shutdown, clean, and `shim_binary --delete`)
+// When running in sandbox mode, shim expected to implement `SandboxService`.
+// Shim lifetimes are now managed manually via sandbox API by the containerd's client.
 type Controller interface {
 	// Start will start new sandbox instance.
 	// containerd will run new shim runtime instance and will invoke Start to create a sandbox process.