# Live momentum signal vs baseline (5m / 30m / 1h windows)

`GET https://flow-api.skylit.ai/v1/flow/{ticker}/momentum`

API: Flowseeker. Credits: 3.

Compares the current 5-minute, 30-minute, and 1-hour flow against the
trailing per-time-of-day baseline (`/v1/flow/{ticker}/baseline`).
Returns z-scores for the 5-minute window and a one-token `trend`
classification.

## Authentication

Send your Skylit API key as a bearer token: `Authorization: Bearer <key>`. No other header is accepted.

## Parameters

| Name | In | Type | Required | Description |
| --- | --- | --- | --- | --- |
| `ticker` | path | string | yes | Underlying ticker symbol (uppercase, e.g. `SPY`, `AAPL`). |
| `as_of` | query | string | no | Replay anchor. Accepts RFC 3339 or Unix seconds. Defaults to "now". |
| `lookback_days` | query | integer | no | Trailing window size in trading days. (default `20`; min 1; max 30) |
| `min_dte` | query | integer | no |  (min 0) |
| `max_dte` | query | integer | no |  (min 0) |

## Example request

```bash
curl "https://flow-api.skylit.ai/v1/flow/SPY/momentum" \
  -H "Authorization: Bearer $SKYLIT_API_KEY"
```

## Responses

### 200

Live momentum metrics + signal.

Shape (placeholder values):

```json
{
  "data": {
    "ticker": "string",
    "asOf": "string",
    "current5m": {
      "tradeCount": 0,
      "premium": 0,
      "bullishPremium": 0,
      "bearishPremium": 0,
      "netPremium": 0,
      "fir": 0
    },
    "current30m": {
      "tradeCount": 0,
      "premium": 0,
      "bullishPremium": 0,
      "bearishPremium": 0,
      "netPremium": 0,
      "fir": 0
    },
    "current1h": {
      "tradeCount": 0,
      "premium": 0,
      "bullishPremium": 0,
      "bearishPremium": 0,
      "netPremium": 0,
      "fir": 0
    },
    "baseline": {
      "timeOfDay": "string",
      "lookbackDays": 0,
      "daysInBaseline": 0,
      "avg5mPremium": 0,
      "stddev5mPremium": 0,
      "avg5mFir": 0,
      "stddev5mFir": 0
    },
    "signals": {
      "firZscore5m": 0,
      "premiumZscore5m": 0,
      "trend": "accelerating",
      "interpretation": "string"
    },
    "queryTimeMs": 0
  },
  "meta": {
    "timestamp": "string",
    "requestId": "d7574836"
  }
}
```

### 400

Request validation failed.

invalidParam:

```json
{
  "error": {
    "code": "BAD_REQUEST",
    "message": "Invalid parameter 'timeframe': must be one of [1m, 5m, 15m, 1h, 4h, 1d, 1w, 1M]"
  }
}
```

### 401

Missing or invalid API key.

missingKey:

```json
{
  "error": {
    "code": "UNAUTHORIZED",
    "message": "Authentication required"
  }
}
```

### 402

The account's shared Skylit credit balance is lower than this route's cost. Top up to continue. Carries `X-Credits-Remaining: 0`.

Headers: `X-Credits-Remaining`.

outOfCredits:

```json
{
  "error": {
    "code": "insufficient_credits",
    "message": "Out of credits. Top up to continue making requests."
  }
}
```

### 403

API key invalid, revoked or expired, or the account's API access is suspended (`account_suspended`).

accountSuspended:

```json
{
  "error": {
    "code": "account_suspended",
    "message": "API access has been suspended for this account. Contact support."
  }
}
```

### 429

Per-minute rate limit exceeded.

Headers: `Retry-After`.

tooFast:

```json
{
  "error": {
    "code": "RATE_LIMITED",
    "message": "Rate limit of 100 req/min exceeded. Retry after 18s."
  }
}
```

### 503

Underlying data source temporarily unavailable, or the credit balance could not be verified (`credit_check_failed`). Safe to retry.

ingestionLag:

```json
{
  "error": {
    "code": "UNAVAILABLE",
    "message": "Live feed is degraded; please retry in a few seconds."
  }
}
```

creditCheckFailed:

```json
{
  "error": {
    "code": "credit_check_failed",
    "message": "Could not verify credit balance. Please retry."
  }
}
```