> ## Documentation Index
> Fetch the complete documentation index at: https://rekko.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Signals

> Anatomy of a trading signal — recommendation, edge, sizing, and risk.

A **signal** is an actionable trading recommendation with position sizing. It's the output of `POST /v1/signals` and combines a full analysis with Kelly-derived sizing.

## The Signal object

```json theme={null}
{
  "platform": "kalshi",
  "market_id": "KXFED-26MAR19",
  "title": "Will the Fed cut rates at the March 2026 meeting?",
  "recommendation": "BUY_YES",
  "target_price": 0.58,
  "edge": 0.12,
  "confidence": 0.73,
  "risk_rating": "medium",
  "size_pct": 0.042,
  "time_horizon": "days",
  "hedge": "Buy NO on KXFED-26MAR26 at 0.82",
  "freshness": "fresh",
  "generated_at": "2026-03-24T14:30:00Z",
  "expires_at": "2026-03-25T14:30:00Z"
}
```

## Recommendation types

| Value      | Meaning                                                              |
| ---------- | -------------------------------------------------------------------- |
| `BUY_YES`  | The event is more likely than the market implies — buy YES contracts |
| `BUY_NO`   | The event is less likely than the market implies — buy NO contracts  |
| `NO_TRADE` | Edge is too small or confidence too low to justify a position        |

## Edge

The `edge` field is the core of every signal:

```
edge = estimated_probability - market_price
```

* **Positive edge** → market underprices the event → `BUY_YES`
* **Negative edge** → market overprices the event → `BUY_NO`
* **Near-zero edge** → no actionable opportunity → `NO_TRADE`

Example: if Rekko estimates 74% probability but the market prices it at 62%, the edge is `+0.12` (12 percentage points).

## Position sizing (Kelly criterion)

The `size_pct` field is a Kelly-derived position size as a fraction of your bankroll:

* `0.042` means "risk 4.2% of your bankroll on this trade"
* Accounts for edge magnitude, confidence, and risk rating
* Conservative half-Kelly by default — designed to avoid ruin

<Warning>
  `size_pct` is a suggestion, not financial advice. Always apply your own risk management.
</Warning>

## Risk ratings

| Rating   | Meaning                                                                     |
| -------- | --------------------------------------------------------------------------- |
| `low`    | Well-understood event, high source quality, multiple confirming signals     |
| `medium` | Moderate uncertainty, mixed signals, or limited source coverage             |
| `high`   | Significant uncertainty, potential for insider information, or thin markets |

## Time horizon

| Value   | Meaning                                                      |
| ------- | ------------------------------------------------------------ |
| `hours` | Signal is time-sensitive — act quickly or edge may evaporate |
| `days`  | Edge likely persists for 1-7 days                            |
| `weeks` | Structural mispricing, slower to correct                     |

## Signal expiry

Always check `expires_at` before acting. After this timestamp, the signal is stale and should not be traded. Market conditions may have changed.

## Requesting a signal

```bash theme={null}
curl -X POST https://api.rekko.ai/v1/signals \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"platform": "kalshi", "market_id": "KXFED-26MAR19"}'
```

<Tip>
  Signals include a full analysis under the hood. If you only need the analysis without sizing, use the [Analysis Pipeline](/concepts/analysis-pipeline) instead — it's a cheaper INSIGHT-tier call.
</Tip>

## Portfolio-aware signals

For position-adjusted sizing that accounts for correlation with your existing holdings, use `POST /v1/signals/portfolio`. Pass your current positions and bankroll to get adjusted sizing, concentration warnings, and hedge recommendations.

<Card title="Portfolio Signal endpoint" icon="chart-pie" href="/api-reference/strategy/portfolio-signal">
  Full endpoint documentation with playground.
</Card>