Yeachan-Heo/oh-my-codex · error · Error

Missing setup install mode value after --install-mode. Expec

Error message

Missing setup install mode value after --install-mode. Expected one of: legacy, plugin

What it means

The --install-mode flag requires a following value (legacy or plugin). The error fires when --install-mode is the last argument or the next token starts with `-` (looks like another flag).

Source

Thrown at src/cli/index.ts:593

      );
    }
    value = next;
  };

  for (let index = 0; index < args.length; index += 1) {
    const arg = args[index];
    if (arg === "--plugin") {
      setValue("plugin", arg);
      continue;
    }
    if (arg === "--legacy") {
      setValue("legacy", arg);
      continue;
    }
    if (arg === "--install-mode") {
      const next = args[index + 1];
      if (!next || next.startsWith("-")) {
        throw new Error(
          `Missing setup install mode value after --install-mode. Expected one of: legacy, plugin`,
        );
      }
      if (next !== "legacy" && next !== "plugin") {
        throw new Error(
          `Invalid setup install mode: ${next}. Expected one of: legacy, plugin`,
        );
      }
      setValue(next, arg);
      index += 1;
      continue;
    }
    if (arg.startsWith("--install-mode=")) {
      const next = arg.slice("--install-mode=".length);
      if (next !== "legacy" && next !== "plugin") {
        throw new Error(
          `Invalid setup install mode: ${next}. Expected one of: legacy, plugin`,
        );

View on GitHub (pinned to 3ad79a8a6f)

Solutions

1. Append a valid value: `--install-mode legacy` or `--install-mode plugin`
2. Use the inline form `--install-mode=plugin`

Example fix

# before
omx setup --install-mode
# after
omx setup --install-mode=plugin

if (args.includes('--install-mode')) {
  const i = args.indexOf('--install-mode');
  const v = args[i + 1];
  if (!v || v.startsWith('-')) throw new Error('missing value');
}

const isSetupInstallMode = (v: unknown): v is 'legacy' | 'plugin' => v === 'legacy' || v === 'plugin';

When it happens

Trigger: `omx setup --install-mode` at end of args, or `--install-mode --scope project`.

Common situations: Truncated commands, shell history editing, or scripts conditionally appending the value that ends up empty.

Related errors

• Missing setup scope value after --scope. Expected one of: ${
• Usage: omx auth add <slot> [--device-auth|--with-api-key|--w
• Usage: omx auth use <slot>
• Missing --task.
• Missing --handoff-json.

AI-assisted analysis of Yeachan-Heo/oh-my-codex@3ad79a8a6f (2026-08-27). Data as JSON: /api/errors/64a295e933251f24. Report an issue: GitHub.