QuantLogix Signal API

Real-time multi-factor stock signals for any US equity or ETF. One API call — composite intelligence from technical analysis, momentum, fundamentals, microstructure, and options flow.

Authentication

All API requests require an API key. Pass it via:

# Header (recommended)
curl -H "X-API-Key: ql_your_key_here" https://quantlogix.ai/api/v1/signal?ticker=NVDA

# Query parameter
curl https://quantlogix.ai/api/v1/signal?ticker=NVDA&apikey=ql_your_key_here

API Access

API access is available to Pro and Institutional subscribers. Generate keys from your profile page.

Endpoints

GET /api/v1/signal

Real-time composite signal for any US stock or ETF.

Parameter	Type	Description
ticker	string	Stock or ETF ticker symbol (required)

Response:

{
  "ticker": "NVDA",
  "signal": "Bullish",
  "composite_score": 72,
  "confidence": 55,
  "scores": {
    "technical": { "score": 78, "weight": 0.55, "details": { "rsi": 58.3, "sma_20": 132.45, "sma_50": 128.90, "sma_200": 115.20, "macd_histogram": 1.234 } },
    "momentum": { "score": 65, "weight": 0.45, "details": { "change_pct": 2.15, "volume_ratio": 1.42 } }
  },
  "price": { "current": 135.50, "prev_close": 132.75, "change": 2.75, "change_pct": 2.07, "vwap": 134.20, "volume": 45200000, "after_hours": 136.10 },
  "indicators": { "rsi": 58.3, "sma_20": 132.45, "sma_50": 128.90, "sma_200": 115.20, "macd_histogram": 1.234 },
  "microstructure": { "score": 68, "health": { "label": "Healthy" }, "bias": { "direction": "Bullish", "strength": 3 } },
  "timestamp": "2026-03-31T12:00:00.000Z"
}

GET /api/v1/microstructure

Market microstructure analysis — VPIN, Amihud illiquidity, Kyle's lambda, order flow, smart money, institutional flow. Requires Basic tier or higher.

Parameter	Type	Description
ticker	string	Stock or ETF ticker symbol (required)

Response includes: VPIN, Amihud Illiquidity, Kyle's Lambda, Roll Spread, Bid-Ask Spread, Order Flow Imbalance, RVOL, HV 30-Day, Intraday Volatility, Point of Control, Smart Money Index, Price Efficiency, Volatility Regime, Institutional Flow (buy/sell %), Volume Profile, Hourly Volume Distribution, Cumulative Volume Delta.

GET /api/v1/news

Multi-source aggregated news — Polygon, Finnhub, Yahoo Finance. Deduplicated and sorted by date. Requires Basic tier or higher.

Parameter	Type	Description
ticker	string	Stock or ETF ticker symbol (required)
limit	integer	Max articles to return (default 10, max 50)

Signal Values

Signal	Score Range	Meaning
Bullish	58-100	Positive technical + momentum alignment, favorable microstructure
Neutral	42-57	Mixed signals, no clear directional bias
Bearish	0-41	Negative technicals, bearish momentum, sell pressure

Rate Limits

Tier	Per Minute	Monthly	Endpoints
Pro	60	10,000	Signal, News
Institutional	300	Unlimited	All (Signal, Microstructure, News, Options, Batch)

Pro vs Institutional Response

Data	Pro	Institutional
Signal (Bullish/Neutral/Bearish)	Yes	Yes
Composite score + confidence	Yes	Yes
Technical + Momentum scores	Scores only	Full details
RSI, SMA 20/50/200, MACD	Yes	Yes
Fundamental score + details	—	Yes
Options flow + details	—	Yes
Microstructure (VPIN, OFI, smart money)	—	Yes (15 metrics)
Institutional flow (buy/sell %)	—	Yes
Volume profile + hourly distribution	—	Yes
Cumulative volume delta	—	Yes
Market cap + sector	—	Yes

Rate limit headers are included in every response:

X-RateLimit-Limit: 60
X-RateLimit-Monthly: 10000
X-API-Tier: pro

Error Codes

Status	Meaning
400	Bad request — missing or invalid ticker
401	Unauthorized — missing or invalid API key
403	Forbidden — endpoint requires higher tier
404	Ticker not found
429	Rate limit exceeded
500	Server error

Code Examples

Python

import requests

response = requests.get(
    "https://quantlogix.ai/api/v1/signal",
    params={"ticker": "NVDA"},
    headers={"X-API-Key": "ql_your_key_here"}
)
signal = response.json()
print(f"{signal['ticker']}: {signal['signal']} ({signal['composite_score']}/100)")

JavaScript

const res = await fetch("https://quantlogix.ai/api/v1/signal?ticker=NVDA", {
  headers: { "X-API-Key": "ql_your_key_here" }
});
const signal = await res.json();
console.log(`${signal.ticker}: ${signal.signal} (${signal.composite_score}/100)`);

cURL

curl -H "X-API-Key: ql_your_key_here" \
  "https://quantlogix.ai/api/v1/signal?ticker=AAPL"