nanocoai/nanoclaw · error · Error

--prompt is required

Error message

--prompt is required

What it means

Thrown by `createTask` when a group was resolved but `--prompt` is empty. A task series is driven by either a prompt or a script; this code path (the prompt-based one) requires a non-empty prompt string, which is what the agent executes on each run/recurrence.

Source

Thrown at src/cli/resources/tasks.ts:145

function selectLiveTasks(mailbox: InboundMailbox, status?: TaskStatus): TaskRow[] {
  return mailbox.listLiveTasks(status);
}

function selectTask(mailbox: InboundMailbox, id: string): TaskRow | undefined {
  return mailbox.getTask(id);
}

function taskId(args: Record<string, unknown>): string {
  const id = str(args.id);
  if (!id) throw new Error('task series id is required');
  return id;
}

async function createTask(args: Record<string, unknown>, ctx: CallerContext) {
  const group = groupArg(args, ctx);
  if (!group) throw new Error('--group is required');
  const prompt = str(args.prompt);
  if (!prompt) throw new Error('--prompt is required');
  const recurrence = normalizeNullableString(args.recurrence) ?? null;
  const script = normalizeNullableString(args.script) ?? null;
  const prepared = prepareScheduledTask({
    name: str(args.name),
    prompt,
    recurrence,
    processAfter: str(args.process_after),
    script,
    dangerouslyOverrideRecurrenceLimit: bool(args.dangerously_override_recurrence_limit),
    timezone: await resolveGroupTimezone(group),
  });
  const { session, row } = await createScheduledTask(group, prepared, {
    originSessionId: ctx.caller === 'agent' ? ctx.sessionId : null,
  });
  return toOutput(session, row);
}

/**

View on GitHub (pinned to 294ef2aee8)

Solutions

1. Add the prompt: `ncl tasks create --group g --prompt "..." --name x`
2. For script tasks, pass `--script <path>` instead of --prompt
3. In scripts, guard: `[ -n "$PROMPT" ] || { echo 'prompt missing'; exit 1; }`

Example fix

# before
ncl tasks create --group grp_123 --name daily-report
# after
ncl tasks create --group grp_123 --name daily-report --prompt "Summarize yesterday's logs"

const prompt = String(process.env.TASK_PROMPT ?? '').trim();
if (!prompt) throw new Error('tasks create needs a non-empty --prompt (or --script)');
await execNcl(['tasks', 'create', '--group', group, '--prompt', prompt]);

const isNonEmptyPrompt = (p: unknown): p is string =>
  typeof p === 'string' && p.trim().length > 0;

When it happens

Trigger: Running `ncl tasks create --group g --name x` with no --prompt (and no script path); passing `--prompt ''` or an unset shell variable; whitespace/quote mistakes that leave args.prompt empty.

Common situations: Shell scripts where $PROMPT is empty due to a missing export; intending a script-based task but forgetting --script (prompt and script are the two mutually exclusive drivers — omitting both hits this error if prompt is checked first); prompt passed after a `--` separator or inside the wrong quotes.

Understand the failure class

Background: Missing required parameter errors: what 'X is required' and 'the required X param is missing' mean, and how to fix them — this error's family across 27 libraries.

Related errors

• --status must be pending or paused
• task series id is required
• --group is required
• --${column.name.replace(/_/g, '-')} must be true or false
• ${col.name} must be one of: ${col.enum.join(', ')}

AI-assisted analysis of nanocoai/nanoclaw@294ef2aee8 (2026-08-28). Data as JSON: /api/errors/29f9001a80e3e96c. Report an issue: GitHub.