Yeachan-Heo/oh-my-codex · warning

Usage: omx exec inject <session-id> --prompt <text> [--actor

Error message

Usage: omx exec inject <session-id> --prompt <text> [--actor <name>] [--json]

What it means

Usage error from parseExecInjectArgs when the `omx exec inject` CLI is invoked without a session id positional argument. The parser takes the first positional as the session id; if it is missing or whitespace-only, this usage string is thrown instead of attempting anything.

Source

Thrown at src/exec/followup.ts:365

}

export function formatInjectExecFollowupSuccess(result: InjectExecFollowupResult): string {
  return [
    `Queued exec follow-up ${result.queued.id} for session ${result.queued.session_id}.`,
    `Queue: ${result.queuePath}`,
    "Delivery: next Stop hook checkpoint; no tmux pane input was sent.",
  ].join("\n");
}

export function parseExecInjectArgs(args: string[]): {
  sessionId: string;
  prompt: string;
  actor?: string;
  json: boolean;
} {
  const [, sessionIdRaw, ...rest] = args;
  const sessionId = sessionIdRaw?.trim();
  if (!sessionId) throw new Error("Usage: omx exec inject <session-id> --prompt <text> [--actor <name>] [--json]");

  let prompt = "";
  let actor: string | undefined;
  let json = false;
  for (let i = 0; i < rest.length; i += 1) {
    const arg = rest[i]!;
    if (arg === "--json") {
      json = true;
    } else if (arg === "--prompt") {
      const value = rest[i + 1];
      if (!value) throw new Error("Missing value after --prompt");
      prompt = value;
      i += 1;
    } else if (arg.startsWith("--prompt=")) {
      prompt = arg.slice("--prompt=".length);
    } else if (arg === "--prompt-file") {
      const value = rest[i + 1];
      if (!value) throw new Error("Missing path after --prompt-file");

View on GitHub (pinned to 3ad79a8a6f)

Solutions

1. Provide the session id as the first positional: `omx exec inject <session-id> --prompt <text>`.
2. If using a variable, verify it is non-empty first: `[ -n "$SESSION_ID" ] || exit 1`.
3. Put the session id before all flags to avoid it being parsed as a flag value.
4. Re-check quoting/quoting of arguments in scripts and CI templates.

Example fix

# before
omx exec inject --prompt "rerun the tests"

# after
omx exec inject "$SESSION_ID" --prompt "rerun the tests"

const sessionId = process.env.SESSION_ID?.trim();
if (!sessionId) { console.error('SESSION_ID is required'); process.exit(1); }
runCli(['exec', 'inject', sessionId, '--prompt', text]);

function isSessionIdArg(v: string | undefined): v is string {
  return typeof v === 'string' && v.trim().length > 0 && !v.startsWith('-');
}

catch (e) { if (e instanceof Error && e.message.startsWith('Usage: omx exec inject')) { console.error(e.message); process.exit(2); } throw e; }

When it happens

Trigger: Running `omx exec inject` with no arguments; passing only flags (e.g. `omx exec inject --prompt hi`) so the first token is consumed as a flag, not a session id; passing a session id of only whitespace; shell quoting that drops the argument.

Common situations: Shell script passes an unset $SESSION_ID variable; user copies the example command but deletes the id placeholder; flags placed before the positional id get consumed as the id slot value incorrectly; CI template renders an empty id.

Understand the failure class

Background: "no subcommand specified" and "... is required": CLI errors when a required argument is missing — this error's family across 13 libraries.

Related errors

• Missing value after --prompt
• Missing path after --prompt-file
• Missing value after --actor
• Unknown exec inject argument: ${arg}
• Unknown adapt argument: ${arg}

AI-assisted analysis of Yeachan-Heo/oh-my-codex@3ad79a8a6f (2026-08-27). Data as JSON: /api/errors/4556358730a43421. Report an issue: GitHub.