Some researchers suggest that depression may be adaptive. For example, depression may provide an opportunity to assess our capabilities, learn from past failures, u-igger personal change, and allocate activity away from futile goals. There are a variety of signature phenomena associated with depression, such as stable, global, and internal styles of failure explanation, a cognitive loop of failure-related rumination, lowered self-esteem and self-efficacy, and increased negative generalization and depressive realism. DEPlanner is presented, a simulated agent that adapts to failure in a simulated environment and exhibits eight targeted signature phenomena of depression.