Angelina Jolie and Brad Pitt's Child Visitation Changes in Hands of Therapist

Brad Pitt's child custody arrangement with Angelina Jolie is in the hands of one man ... according to docs filed by Jolie.

Right now, the exes and their 6 kids are operating under a temporary custody deal agreed upon by both sides. As we've reported ... she has primary custody and Brad gets monitored visits, but the docs Angelina filed spell out the details.

According to the docs ... when and how Brad sees the children is determined by a psychologist who specializes in child custody issues. The deal says, the "frequency and conditions of the therapeutic visitation shall be determined by Ian Russ, Ph.D." Brad and Angie also must participate in group therapy sessions with the kids.

The terms of this deal must stay in place until there's a court order, or both parents agree to change it.

Additionally, the docs say Brad will submit to random drug and alcohol tests at least 4 times per month.

Pitt and Jolie made this arrangement in October, while Brad was still under investigation by the DCFS, but as we've reported ... the agency cleared him of any wrongdoing a month ago.

Jolie's filing essentially memorializes the temporary deal with the court. The judge signed it on Friday.