A short intention needs a visible endpoint
A plan to play for a little while can be difficult to interpret once a game presents another task. A more concrete intention names what you want to do: inspect the controls, complete an available tutorial section or explore one branch. Choose an endpoint you can recognize from the game itself, rather than a vague condition such as finally feel satisfied.
Separate a task endpoint from a time limit
You can have a time boundary and a task boundary, but they serve different purposes. A timer tells you when your available interval ends; a task tells you what the session is about. If the task turns out to be longer than expected, the time boundary still matters. Do not turn an uncertain completion estimate into a promise that the game will fit the interval.
For a fictional example, you might choose to learn how one input works before leaving. The endpoint is being able to describe the input and its visible response, not necessarily winning a challenge that uses it. That gives the session a purpose which does not depend on an unknown number of attempts or a guaranteed successful result.
Check what the game preserves
If you expect to continue later, read the actual save or restart information. Reaching a location does not prove that it will remain available after closing the game. A local history list on a website also does not establish that the embedded game's progress is saved. Keep navigation records, game state and personal notes separate in your planning.
Where saving is unclear, choose a session purpose that remains useful even if the state resets. Understanding a rule or deciding whether the activity suits you can still be a complete outcome. This does not make the game interruption-friendly; it simply avoids making your entire purpose depend on a feature you have not confirmed.
End by preserving the next question
Before stopping, note one thing you would want to do next and any information needed to recognize it. A brief note such as inspect the unvisited branch beside the marked door is more useful than continue later. You can then leave with a clear boundary. The session does not need a perfect result to have fulfilled the specific purpose you chose at the beginning.