Codex Exec — one-shot runtime adapter

Codex Exec — one-shot runtime adapter

Run exactly one caller-supplied Codex prompt as one process and capture its result. This skill does not choose work, retry, validate or continue. One prompt, one process, one captured artifact keeps every output byte traceable to one invocation.

Rules that change the command

• Sandbox from declared effects. -s read-only for review or analysis, workspace-write only for authorized edits, and network or wider access only when the caller explicitly requires those effects. "In case it needs it" is not a declared effect.
• Close stdin. codex exec reads the prompt from stdin when no prompt argument is given, and appends piped stdin to a prompt argument. A non-TTY run (CI, a script) with an open stdin can wait forever: the stdin hang. Feed the prompt on stdin and let it end, or redirect </dev/null.
• One deadline, never renewed. Fix one absolute deadline before the first attempt. Each invocation, including any retry the caller decides to make, gets only the time left before that deadline. A retry never gets a fresh budget: a loop that gives each attempt its own new timeout has silently multiplied the caller's bound. A missing, zero, negative or malformed bound prevents launch; an expired deadline stops before dispatch.
• No retry here. Report a timeout, error or empty output as it is. Another invocation is the caller's decision, under the same deadline.
• Capped capture, typed exit. Capture output to a file under a byte cap and report the exit status. A timeout is not a result.

Run it

In an AgentOps source checkout, use the guarded library. It enforces the deadline, the combined output cap (10 MiB default), process-group cleanup and echo detection:

# DEADLINE_EPOCH: absolute Unix time fixed once by the caller and reused by
# every invocation in its scope.
. "$AGENTOPS_ROOT/scripts/lib/codex-exec.sh"
CODEX_EXEC_DIR="$WORKSPACE" CODEX_EXEC_SANDBOX=read-only \
CODEX_EXEC_PROMPT_FILE="$PROMPT_FILE" CODEX_EXEC_DEADLINE_EPOCH="$DEADLINE_EPOCH" \