CRISPR-Cas systems are revolutionary tools with practical uses ranging from genetic engineering to gene drives. A key aspect of utilizing CRISPR technology effectively is the discovery and development of anti-CRISPRs, which are phage-derived proteins that can strongly inhibit CRISPR functions. However, finding naturally occurring anti-CRISPRs is difficult, and many important Cas effectors lack inhibitors to control their activity. This study presents a method using de novo protein design to create novel proteins that regulate CRISPR-Cas activity. The research shows that AI-designed anti-CRISPRs (AIcrs) can specifically and powerfully inhibit the target protein, CRISPR-Cas13. The study includes thorough design validation and demonstrates the use of AIcrs in managing the anti-phage activity of CRISPR-Cas13 in bacteria. The ability to quickly design custom inhibitors for CRISPR-Cas systems will aid in the development of gene editors for clinical applications and help prevent their misuse.