Agents act on the world through tools, and tools have real consequences. A file written cannot be unwritten without a record of what it replaced. A shell command executed leaves state. Safety infrastructure is a prerequisite for working at speed without catastrophic loss.

Git and version control remain the primary safety layer in agentic engineering, despite the checkpoint systems built into modern ADEs. Across sessions and in collaborative environments, Git is the only audit trail that persists, the only history that is human-readable and independently verifiable.

The Git practices that matter in an agentic workflow are specific. Committing before invoking an agent on a non-trivial task creates a clean restore point. Atomic commits whose messages explain why rather than only what make the agent’s trajectory readable after the fact. Branch discipline gives the human a safe space to evaluate agent output.

Trajectory management is the judgment skill that determines whether a session ends with a usable result or a compounding mess. Signals indicate a trajectory is drifting; interventions correspond to each signal.