Displaying a custom label for each individual point

mpldatacursor’s point_labels functionality can be emulated with an event handler that sets the annotation text with a label selected from the target index.

import matplotlib.pyplot as plt
import mplcursors
import numpy as np

labels = ["a", "b", "c", "d", "e"]
x = np.array([0, 1, 2, 3, 4])

fig, ax = plt.subplots()
line, = ax.plot(x, x, "ro")
mplcursors.cursor(ax).connect(
    "add", lambda sel: sel.annotation.set_text(labels[sel.index]))

plt.show()