Atlas is source control for coding agents. Every agent run produces checkpoints: commits are linked back to the session that made it alongside the prompts, tool calls, and reasoning. You see which agent did exactly what and why. Run Claude Code, Codex, Atlas's own agent, or anything from the ACP registry side by side against the same codebase, with shared memory so switching agents mid-task doesn't mean starting over. - Every commit, explained. A checkpoint links a commit back to the session that produced it: prompts, tool calls, and file changes kept together, queryable months later. - Run an