Mr Habre is accused of ordering the killing of 40,000 people during his rule in the 1980s, charges which he denies.
The trial was adjourned in July after Mr Habre and his lawyers refused to speak to the court.
It marks the first time one African country has prosecuted the former leader of another.
If he refuses to recognise his newly appointed legal team, the judge will have to decide whether to adjourn proceedings again or try Mr Habre against his will, reports BBC West Africa correspondent Thomas Fessy, who is in court.
With many Africans denouncing the International Criminal Court as neo-colonial, this trial is considered a chance for the continent to show it can hold its leaders to account, our correspondent adds.
The trial follows a 25-year campaign to bring him to justice.
Many of Mr Habre's alleged victims have been calling for him to face justice since his overthrow and exile in Senegal in 1990.
