Key Takeaways
Identity is cognitive architecture, not decoration. A well-designed identity produces behavior that a job description cannot replicate, because it shapes judgment, priorities, and reasoning patterns across novel situations.
Six components, one system. Name creates persistence. Metaphor provides depth. Core Belief drives trade-offs. Cognitive Posture shapes engagement. Primary Obligation creates focus. Identity Anchor enables recovery. Remove any one and the identity has a specific, predictable vulnerability.
The Job Description Test. If you can replace the full identity with a one-liner and get the same behavior, the identity isn't doing work. The gap between the job description and the full identity is the identity's actual contribution.
Identity handles the unexpected. Instructions cover scenarios you anticipated. Identity covers everything else. In production, "everything else" is where most of the value is.
Build, test, break, revise. Your v1.0 identity is a hypothesis. The stress test is the first experiment. What breaks reveals what needs to be strengthened. This is how agents evolve, starting with identity.