Pursuant to a plea agreement, Angel Rene Hernandez pleaded guilty to conspiracy to possess with intent to distribute methamphetamine and was sentenced to 144 months in prison. He contends for the first time on appeal that the district court erred in assigning criminal history points to two of his prior convictions. The Government urges us to enforce the appellate waiver in the plea agreement. Hernandez does not address the appeal waiver in his opening brief, and he has not filed a reply brief to respond to the Government’s argument. We review the validity of the appeal waiver de novo. See United States v. Baymon, 312 F.3d 725, 727 (5th Cir. 2002).

Hernandez waived his right to appeal his sentence unless it was the result of an upward departure, ineffective assistance of counsel, or prosecutorial misconduct. The waiver was knowing and voluntary, as the record shows that Hernandez knew of his right to appeal and that he was giving up that right in the plea agreement. See United States v. Portillo, 18 F.3d 290, 292 (5th Cir. 1994). Because the plain language of the waiver provision applies to Hernandez’s challenge to his criminal his *559 tory category, we enforce the waiver. See United States v. Bond, 414 F.3d 542, 544 (5th Cir. 2005). Counsel for Hernandez is cautioned that pursuing an appeal contrary to a valid waiver is a needless waste of judicial resources that could result in sanctions. See United States v. Gaitan, 171 F.3d 222, 223-24 (5th Cir. 1999).

AFFIRMED.