HKUDS/Vibe-Trading · error · ValueError

source.variables must be an object

Error message

source.variables must be an object

What it means

For playbook sources, source.variables (used by playbook.render) must be a JSON object/Mapping when provided. Arrays, strings, or scalars are rejected because template variables are keyed.

Source

Thrown at agent/src/scheduled_research/service.py:146

        raise ValueError("source and schedule must be objects")
    if not isinstance(delivery_spec, Mapping):
        raise ValueError("delivery must be an object")

    source_type = str(source.get("kind") or "prompt")
    playbook_slug = None
    config: dict[str, Any] = {}
    if source_type == "prompt":
        prompt = str(source.get("prompt") or "").strip()
        if not prompt:
            raise ValueError("source.prompt is required")
    elif source_type == "playbook":
        playbook_slug = str(source.get("playbook_slug") or "").strip()
        if not playbook_slug:
            raise ValueError("source.playbook_slug is required")
        playbook = get_playbook(playbook_slug)
        variables = source.get("variables") or {}
        if not isinstance(variables, Mapping):
            raise ValueError("source.variables must be an object")
        prompt = playbook.render(variables)
        config["playbook"] = playbook_slug
    else:
        raise ValueError("source.kind must be 'prompt' or 'playbook'")

    expression = str(schedule_spec.get("expression") or "").strip()
    timezone = schedule_spec.get("timezone")
    validate_schedule(expression)
    if is_interval_schedule(expression):
        validate_timezone_shape(timezone)
    else:
        validate_timezone(timezone)
    next_run_at = now
    if timezone is not None and not is_interval_schedule(expression):
        next_run_at = next_due(expression, now, timezone)

    end_at = _parse_end_at(draft.get("end_at"))
    if end_at is not None and end_at <= now:

View on GitHub (pinned to 80ffdda44c)

Solutions

1. Send variables as an object: {"topic": "AI", "depth": 3}
2. Omit it or pass null to use no variables
3. If the string case is double-encoding, JSON.parse it client-side before submit

Example fix

// before
{"variables": "{\"topic\": \"AI\"}"}
// after
{"variables": {"topic": "AI"}}

from collections.abc import Mapping
v = draft.get("source", {}).get("variables")
assert v is None or isinstance(v, Mapping)

from collections.abc import Mapping

def variables_valid(src: dict) -> bool:
    v = src.get("variables")
    return v is None or isinstance(v, Mapping)

try:
    propose_create(draft)
except ValueError as e:
    if "variables must be an object" in str(e):
        draft["source"]["variables"] = json.loads(draft["source"]["variables"]) if isinstance(draft["source"].get("variables"), str) else {}

When it happens

Trigger: Sending variables as a list of pairs, a JSON-encoded string, or null-adjacent scalars (note: null/absent defaults to {}).

Common situations: Double-serialized JSON (variables: '{"k":1}'); clients mapping form arrays into the field; API glue code passing **kwargs lists.

Related errors

• playbook {self.slug!r} has no variable {key!r}; declared: {s
• playbook variable {key!r} is {len(text)} chars; the cap is {
• source.playbook_slug is required
• timezone {tz!r} is not a recognized IANA timezone key
• unknown delivery status {raw_status!r}

AI-assisted analysis of HKUDS/Vibe-Trading@80ffdda44c (2026-08-28). Data as JSON: /api/errors/94c31384e550e14d. Report an issue: GitHub.