Here is a video of an agent trying to follow a specific path while also trying to avoid the spherical obstacles:
Some problems with this implementation is that the agent sometimes breakes the physical laws and walks inside the obstacle. Also the steering is jagged which does not look realistic. When a human spots an obstacle it doesn't turn the opposite way like the agent seems to do. Instead it turns just enough to not intersect with the obstacle.
A more smooth implementation of obstacle avoidance is shown in a previous post.
Link to UnitySteer: https://github.com/ricardojmendez/UnitySteer