An identity dependencies graph is a relationship map of identities, permissions, sessions, and trust paths. Instead of treating a login as a single event, it shows how a human user, service account, or AI agent can inherit authority and move through systems.
This matters because many attacks abuse delegated access rather than breaking passwords outright. If credentials are reused, privileges are too broad, or session links are unclear, an attacker can hide inside legitimate-looking activity and reach data or tools they should not access. Defenders use identity graphs to spot transitive trust, excessive permissions, stale sessions, and risky chains of delegation. In practice, the graph helps answer three questions: who authorized this identity, what can it reach, and when should that access stop? It is most useful when paired with least privilege, short-lived credentials, and strong auditing.