# Simple Exponential Smoothing (SES) Forecast

> Simple Exponential Smoothing (SES) Forecast is a paid API for AI agents from agent402.tools, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Applies simple exponential smoothing to a numeric time series and returns level-only forecasts for a specified future horizon

## Facts

- Endpoint: POST https://agent402.tools/api/forecast-ses
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/simple-exponential-smoothing-ses-forecast-a4752f07
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_cvDeNlQHety-hYnIyCm4Y

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability simple-exponential-smoothing-ses-forecast-a4752f07 -d '<json body>'
```

Example prompt: Can you use simple exponential smoothing to forecast the next 12 periods of this monthly sales series — [120, 135, 128, 142, 150, 147, 160, 155, 170, 165, 180, 175, 190] — with an alpha of 0.4?

## When to prefer this

Use this endpoint when you have a stationary time series with no clear trend or seasonality and want a simple, interpretable forecast. Ideal for smoothing noisy data with controllable reactivity via alpha. Prefer over ARIMA or Holt-Winters when simplicity and speed matter more than modeling complex patterns.

## Known failure modes

- Series has fewer than 3 values — returns validation error
- Alpha is outside the (0, 1) range — returns parameter error
- Horizon exceeds 1000 — returns out-of-range error
- Series length exceeds 10000 elements — returns payload too large error
- Non-numeric values in the series — returns type error

## How this service works

Simple exponential smoothing (SES) - level-only forecast for series without trend or seasonality. Higher alpha (closer to 1) tracks recent values aggressively; lower alpha (closer to 0) smooths through noise. Default alpha=0.3 is a common conservative pick; pass an explicit alpha or use forecast-eval to pick the one that minimizes backtest error. Forecast is flat (= last fitted level) for all horizons.

## Output

Returns smoothed forecast values for the requested number of future periods, computed via the SES algorithm applied to the input chronological series with the specified alpha parameter.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "alpha": {
   "type": "number",
   "description": "Smoothing parameter, 0 < alpha < 1 (default 0.3)"
  },
  "values": {
   "type": "array",
   "description": "Numeric series in chronological order (max 10000, min 3)"
  },
  "horizon": {
   "type": "number",
   "description": "Number of future periods to forecast (1 to 1000)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "n": 10,
  "alpha": 0.3,
  "method": "ses",
  "horizon": 3,
  "forecast": [
   {
    "step": 1,
    "point": 45.4431,
    "lower95": 42.7805,
    "upper95": 48.1057
   },
   {
    "step": 2,
    "point": 45.4431,
    "lower95": 42.6633,
    "upper95": 48.2229
   },
   {
    "step": 3,
    "point": 45.4431,
    "lower95": 42.5508,
    "upper95": 48.3354
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/simple-exponential-smoothing-ses-forecast-a4752f07/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent402.tools](https://www.zero.xyz/host/agent402.tools/llms.txt)