A method for performing tasks on items located in a space using a robot, includes receiving an order to perform a task on at least one item and obtaining a pose associated with the at least one item. The pose is in a coordinate system defined by the space and the pose is where the task is to be performed on the at least one item. The method includes navigating the robot toward the pose associated with the at least one item and detecting, when in proximity to the pose, if the pose is obstructed by an object. If the pose is obstructed by an object, halting the robot at a location spaced from the pose and then causing the robot to provide a first signal indicating that the robot is in a holding mode at the location spaced from the pose.