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" ``` Route text you did not author through this channel whatever its size — a diff, file contents, a code comment, a plan or spec, third-party feedback, command output. Keep backticks and `$` out of the quoted argument even in text you wrote, since both stay live inside it. Write the context file with the Write tool so nothing is interpreted on the way in. ## 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 | c...