codex-exec

# Codex Exec Autonomous task execution via the codex CLI. Runs non-interactively. Progress streams to stderr; final result on stdout. ```bash codex exec "task description" < /dev/null ``` For large context, pipe it via stdin. The prompt stays as the argument, context is passed as `<stdin>` automatically: ```bash cat context.txt | codex exec "question about the context" ``` ## Sandbox **All `codex` Bash calls require `dangerouslyDisableSandbox: true`** (network access to OpenAI API). Without it, codex crashes with an `Operation not permitted` panic from the `system-configuration` crate before the model runs. ## Stdin Gotcha Codex reads from stdin whenever stdin is non-TTY (per `codex exec --help`: "If stdin is piped and a prompt is also provided, stdin is appended as a `<stdin>` block"). In subagent and subprocess contexts the harness leaves stdin connected to a pipe that never EOFs, so a bare `codex exec "..."` hangs forever, printing only `Reading additional input from stdin...`. Always redirect stdin on non-piped invocations: ```bash codex exec "task description" < /dev/null ``` The piped form (`cat context.txt | codex exec "..."`) is safe — `cat` closes the pipe after the file, sending EOF. ## Permission Levels | Level | Flag | When to Use | |-------|------|-------------| | Read-only (default) | *(none)* | Analysis, code reading, generating reports | | Workspace write | `--sandbox workspace-write` | Editing files within the project | | Full access | `--sandbox...