In my game I use a navmesh and navagents. However, there are also objects with StaticBody3D in the area. The navagents sometimes calculate paths that are so close to the edge that the colliders of the agents collide with those of the objects around them and the agent gets stuck in that spot.
You need to bake the navigation mesh with an agent radius that is at least as large as your collision shape plus some margin to account for physics sliding and path desired distance on the agent.
