affaan-m/ECC · error · Error

--json may only be provided once

Error message

--json may only be provided once

What it means

parseArgs counts occurrences of the --json flag; providing it more than once throws this error. The flag is a toggle for JSON output and duplicates are treated as a caller mistake rather than silently deduplicated.

Solutions

1. Remove the duplicate --json so it appears at most once
2. In wrapper scripts, deduplicate before invoking: args = [...new Set(args.filter(a => a !== '--json')), ...(needsJson ? ['--json'] : [])]
3. Check where defaults and user args are merged and de-dupe the flag there

Example fix

// before
const args = [...baseArgs, '--json', ...userArgs]; // userArgs already has --json
// after
const args = baseArgs.includes('--json') || userArgs.includes('--json')
  ? [...baseArgs, ...userArgs.filter(a => a !== '--json'), '--json']
  : [...baseArgs, ...userArgs];

function dedupeJson(args) {
  const count = args.filter(a => a === '--json').length;
  if (count > 1) throw new Error('--json provided more than once');
  return args;
}

try {
  runIto(args);
} catch (e) {
  if (e.message === '--json may only be provided once') {
    runIto([...new Set(args.filter(a => a !== '--json')), '--json']);
  } else throw e;
}

When it happens

Trigger: Running `ecc ito status --json --json`, or composing argument arrays in scripts where both a wrapper and the inner command append --json, resulting in two occurrences.

Common situations: Shell wrappers that prepend their own --json on top of a user-supplied one; concatenating default flags arrays with user flags containing --json; fat-fingering the flag twice.

Understand the failure class

Background: "Unknown argument", "Invalid value", and "must be one of": invalid CLI argument errors explained — this error's family across 35 libraries.

Related errors

• all overlays must be readable local files
• all takes must be readable local files
• Arguments must not contain NUL bytes.
• asset name must be a simple filename stem (letters, digits…
• At least one guided harness must be selected

AI-assisted analysis of affaan-m/ECC@8321021c54 (2026-09-16). Data as JSON: /api/errors/1fa29443c5cd590a. Report an issue: GitHub.

Appendix: source

Thrown at scripts/ito.js:161

  if (
    args.length === 0
    || args.includes("--help")
    || args.includes("-h")
  ) {
    return Object.freeze({ help: true, invocationArgs: [] });
  }

  if (environment.ECC_DRY_RUN === "1" || args.includes("--dry-run")) {
    throw new Error(
      "Itô compute has no paper or dry-run success mode. No CLI operation was invoked."
    );
  }

  const jsonIndexes = args
    .map((value, index) => (value === "--json" ? index : -1))
    .filter((index) => index >= 0);
  if (jsonIndexes.length > 1) {
    throw new Error("--json may only be provided once");
  }
  const withoutJson = args.filter((value) => value !== "--json");
  const command = withoutJson.shift();
  if (!SUPPORTED_COMMANDS.includes(command)) {
    throw new Error(
      `Unsupported Itô command "${command || "(missing)"}"; ECC permits only login, logout, auth, find, status, and evals.`
    );
  }
  if (command === "auth" && withoutJson.includes("--no-browser")) {
    throw new Error("--no-browser is valid only for ecc ito login; auth is validation-only.");
  }
  if (command === "evals") {
    validateNodeQualificationArgs(withoutJson, environment);
  }

  return Object.freeze({
    help: false,
    invocationArgs: Object.freeze([

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