---
title: "Api V2 Signals Advanced 0Dte-Position-Imbalance Get"
method: GET
path: "/api/v2/signals/advanced/0dte-position-imbalance"
tags: ["Trade Signals (v2)"]
---

# Api V2 Signals Advanced 0Dte-Position-Imbalance Get

`GET /api/v2/signals/advanced/0dte-position-imbalance`

## Request

- Base URL: `https://api.zerogex.io` (the document declares no server; this is the origin it was published from)
- URL: `https://api.zerogex.io/api/v2/signals/advanced/0dte-position-imbalance`
- Auth: HTTP bearer

Same-day-expiry flow tilt — 0DTE call vs put premium imbalance.

Measures when 0DTE call vs put net premium becomes lopsided enough to
forecast short-term drift from dealer hedging. Falls back to all-expiry
flow when 0DTE data is absent, reflected in `flow_source`.

**Logic highlights** (`src/signals/advanced/zero_dte_position_imbalance.py`):
- Buckets 0DTE flow by moneyness (ATM ±0.5%), weighting OTM most:
  `0.6·OTM_call − 0.6·OTM_put + 0.3·ATM_call − 0.3·ATM_put + 0.1·ITM − ...`
- `flow_imbalance = weighted / total_abs` (gated to 0 below $50k gross).
- Combined = `0.55·flow + 0.30·smart_imbalance + 0.15·pcr_tilt`.
- Multiplied by a time-of-day ramp (stronger near close, zero after hours).
- **Triggered when `|score| ≥ 25` (clamped 0.25).**

**Note on time-gating:** `tod_multiplier` zeros after hours — treat as
"inactive," not "neutral."

**Params:** `symbol` (default `SPY`). Returns 404 when no data exists.

**Returns:**
```json
{
  "score": 31.0, "clamped_score": 0.31, "direction": "bullish",
  "triggered": true,
  "signal": "call_heavy",
  "flow_imbalance": 0.42,
  "smart_imbalance": 0.18,
  "context_values": {"...call_net_premium, put_net_premium, otm_call_net, atm_call_net, otm_put_net, atm_put_net, pcr_tilt, put_call_ratio, tod_multiplier, flow_source..."},
  "score_history": [{"score": 31.0, "timestamp": "..."}, "...up to 90"]
}
```

- `score` — [-100, +100].
- `signal` — `"call_heavy"` | `"put_heavy"` | `"balanced"`.
- `triggered` — `true` when `|score| ≥ 25`.
- `flow_imbalance` — [-1, +1]; bucket-weighted net imbalance.
- `smart_imbalance` — [-1, +1]; smart-money subset.
- `flow_source` (in `context_values`) — `"zero_dte"` | `"all_expiry_fallback"`.

**Trader interpretation:**
- `call_heavy` near close with rising momentum → lean long (dealers short 0DTE calls must chase).
- `put_heavy` near close with falling momentum → lean short.
- Warn when `flow_source == "all_expiry_fallback"`: 0DTE picture is inferred, not measured.

**Page design.** Diverging bar chart with four moneyness buckets (OTM/ATM calls vs OTM/ATM puts).
`flow_source` chip + `tod_multiplier` as a clock/progress indicator.

## Query parameters

- `symbol` string

## Response `200`

Successful Response

- EnvelopeAny
  - `data` unknown, required
  - `freshness` Freshness, required: The v2 freshness envelope. Present on every ``/api/v2/*`` response.
    - `evaluated_at` string, date-time, required: When the API evaluated this response (server wall clock, UTC). Endpoint-health signal: advances on every request even when the underlying data is unchanged.
    - `generated_at` string, date-time, required: When the served data was computed. Equals the snapshot stamp for cycle-backed endpoints, or evaluated_at for endpoints computed on demand for this request.
    - `source_timestamp` string, date-time, nullable: Timestamp of the upstream market observation the payload derives from. This is what freshness_status is measured against. Null when the endpoint has no upstream feed or returned no rows.
    - `latest_event_at` string, date-time, nullable: Newest event timestamp present in the payload (last bar, last trade, last scored row). Best-effort on very large responses, which are sampled rather than fully walked.
    - `age_seconds` number, nullable: evaluated_at - source_timestamp, in seconds. Null when source_timestamp is null.
    - `market_session_status` string, required: pre-market | regular | after-hours | closed (US/Eastern).
    - `expected_update_cadence` string, nullable: ISO-8601 duration for how often this endpoint's data is expected to change right now, e.g. PT60S. Null means no updates are expected (weekend, holiday, or a feed that only runs during the session).
    - `expected_update_cadence_seconds` number, nullable: expected_update_cadence as a number of seconds.
    - `cadence_profile` string, required: Identifier of the cadence class this endpoint belongs to, e.g. analytics_cycle. Stable across releases; the seconds behind it may be retuned.
    - `stale_after` string, date-time, nullable: Instant after which this payload should be treated as stale. Null whenever expected_update_cadence is null.
    - `freshness_status` 'fresh' | 'aging' | 'stale' | 'session_closed' | 'static' | 'unknown', required: The rolled-up freshness verdict for one response. ``fresh`` ``source_timestamp`` is within one expected update cadence. ``aging`` Past one cadence but not yet past ``stale_after`` — the grace band that absorbs normal cycle jitter. Not an error; a client that polls faster than the cadence sees this routinely. ``stale`` Past ``stale_after`` while updates *were* expected. This is the actionable state: the feed behind this endpoint is late. ``session_closed`` A feed-backed endpoint whose feed is not due to produce anything right now (weekend, holiday, or a feed that only runs during the session). The payload is the last good value — deliberately NOT reported as ``stale``, because an overnight consumer polling a closed market is not observing a fault and should not page on it. ``static`` The endpoint is not feed-backed at all: completed history, or a result computed from the caller's own inputs. Age here carries no health meaning and never becomes a fault. ``unknown`` No source timestamp could be resolved from the payload (e.g. a pure calculator, an admin endpoint, or an empty result set). A consumer should fall back to ``evaluated_at`` for endpoint health and make no claim about data age.

## Other responses

- `422`: Validation Error

---

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