If you have Extra Attack, you may use this maneuver in place of one attack.

If you are within 20 feet when your animal companion is hit by an attack, you can use your reaction to call out and help it regain its fighting spirit. As long as it is able to hear you, your animal companion regains hit points equal to your level.

When a creature of up to one size category larger than your animal companion makes a melee attack against it, you command your animal companion to respond by harrying the attacker’s movements.

You and your animal companion must both take this stance to gain its benefits.

When a creature makes a weapon attack against your animal companion, your warning causes your companion to shift position, gaining a bonus to AC equal to your proficiency bonus and possibly turning a hit into a miss.

You command your animal companion to switch places with a creature within 5 feet of it.