Codex subagents - Mains

Codex can delegate focused work to subagents. Each worker has its own thread and context; the parent coordinates their tasks and results.

Request a division of work

Use subagents to inspect the authentication change.
Assign separate reviews for correctness, security, and test coverage.
Return one combined list of findings without editing files.

Delegation availability and custom agent profiles follow your installed Codex runtime and configuration. You do not need to add an experimental flag merely to display supported subagent activity in Mains.

Follow activity

Mains shows spawn, send-input, wait, close, and resume activity in the transcript. It resolves worker names and roles where Codex supplies them. The subagent panel shows each worker’s task, status, tool calls, and results. Failed delegation steps appear with their own error, so you can identify which operation failed.

Files and permissions

Workers operate under the parent run’s mode and permission constraints. A separate thread is not a separate checkout. Use worktrees when parallel workers or conversations need independent file edits. Increasing delegation does not grant extra filesystem or connector access.

Continue or stop

Use the parent conversation to revise the task. Stopping the run also stops its active work, including delegated work managed by that run. For voice jobs that open independent visible chats, see Voice conversations; ending the voice call can leave those jobs running.