# Space Weather Intelligence — Kp-Index Forecast

> Space Weather Intelligence — Kp-Index Forecast is a paid API for AI agents from space-weather.use.x402atlas.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Returns NOAA SWPC geomagnetic Kp-index forecast for up to 3 days, with each period labeled as observed, estimated, or predicted.

## Facts

- Endpoint: GET https://space-weather.use.x402atlas.com/forecast
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/space-weather-intelligence-kp-index-forecast-76e72b5d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2dKGp539e8QWILxVvmA_r

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 space-weather-intelligence-kp-index-forecast-76e72b5d
```

Example prompt: Pull the NOAA SWPC geomagnetic Kp-index forecast for the next 3 days and tell me which periods are observed, estimated, or predicted.

## When to prefer this

Choose this endpoint when you need a structured, normalized multi-period Kp-index forecast (1–3 days) from NOAA SWPC with clear period labels (observed/estimated/predicted). Prefer it over raw NOAA feeds when you need clean JSON, built-in staleness detection, and bounded forecast windows. Use sibling endpoints for current real-time conditions or alert messages rather than the forward-looking forecast.

## Known failure modes

- NOAA SWPC source unavailable — stale cached data returned with stale:true flag
- Invalid days parameter (outside 1–3 range) — validation error
- Payment failure (x402) — 402 response requiring USDC payment
- Upstream data delayed — source_age_seconds may be elevated

## How this service works

Space-weather forecast — normalized one-to-three-day NOAA SWPC geomagnetic Kp-index periods labeled observed, estimated, or predicted.

## Output

A JSON object containing normalized Kp-index forecast periods (up to 3 days), each labeled as observed, estimated, or predicted, along with the forecast issuance timestamp, a stale cache flag, source age in seconds, any active warnings, and the applied day-window query parameters.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "days": {
       "type": "integer",
       "default": 3,
       "maximum": 3,
       "minimum": 1,
       "description": "Number of 24-hour periods from retrieval time"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "operation",
      "schema_version",
      "query",
      "issued_at",
      "periods",
      "source",
      "stale",
      "source_age_seconds",
      "warnings"
     ],
     "properties": {
      "query": {
       "type": "object",
       "required": [
        "days"
       ],
       "properties": {
        "days": {
         "type": "integer",
         "maximum": 3,
         "minimum": 1,
         "description": "Applied forecast-day window"
        }
       },
       "description": "Normalized query identity after applying the default day window",
       "additionalProperties": false
      },
      "stale": {
       "type": "boolean",
       "description": "True only when a validated cached snapshot was used"
      },
      "_atlas": {
       "type": "object",
       "required": [
        "docs"
       ],
       "properties": {
        "docs": {
         "type": "string",
         "format": "uri",
         "maxLength": 512,
         "description": "Documentation URL for this bridge"
        },
        "related": {
         "type": "array",
         "items": {
          "type": "object",
          "required": [
           "bridge",
           "url",
           "docs",
           "summary"
          ],
          "properties": {
           "url": {
            "type": "string",
            "format": "uri",
            "maxLength": 512,
            "description": "Related route URL"
           },
           "docs": {
            "type": "string",
            "format": "uri",
            "maxLength": 512,
            "description": "Related bridge documentation UR
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/space-weather-intelligence-kp-index-forecast-76e72b5d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from space-weather.use.x402atlas.com](https://www.zero.xyz/host/space-weather.use.x402atlas.com/llms.txt)