# Greeneris Sea State & Marine Weather Forecast

> Greeneris Sea State & Marine Weather Forecast is a paid API for AI agents from data.greeneris.io, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Returns Mediterranean marine weather forecasts including wave height, period, and direction for named ports or custom lat/lon coordinates, covering up to 7 days ahead.

## Facts

- Endpoint: GET https://data.greeneris.io/v1/sea/state
- 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/greeneris-sea-state-marine-weather-forecast-7649e3ca
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xMAkClj9GRyNdaRbcCjAh

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 greeneris-sea-state-marine-weather-forecast-7649e3ca
```

Example prompt: What will the sea conditions be like at Marseille over the next 3 days — specifically wave height and direction?

## When to prefer this

Choose this endpoint when you need structured, machine-readable Mediterranean marine weather forecasts for named ports (Marseille, Ajaccio, Genoa, etc.) or arbitrary lat/lon coordinates, with wave height summaries and hourly breakdowns. Prefer this over generic weather APIs when nautical or marine-specific variables (wave period, wave direction) are required. Pay-per-call at $0.005 USDC with no account setup needed.

## Known failure modes

- Invalid or out-of-range latitude/longitude returns an error
- Unsupported port name returns an error or empty result
- Forecast days value outside 1-7 range may be rejected or clamped
- HTTP 402 returned if payment not attached — endpoint requires x402 USDC payment before data is served
- Network timeout if upstream Open-Meteo service is unavailable

## How this service works

Hourly sea-state forecast from Open-Meteo Marine wave models: wave height/direction/period, wind waves and swell, up to 7 days, UTC. Query: ?port=marseille|ajaccio|nice|... (12 Mediterranean presets) or ?latitude=43.3&longitude=5.4, plus ?days=1-7 (default 2). Includes a summary block (max wave height next 24h / full horizon). 1h cache. For sailing go/no-go, port ops and routing.

## Output

Returns a JSON object with source attribution, a summary of first-hours wave heights, max wave height over 24h and the full forecast window, the resolved location (port name or lat/lon), hourly units, and the number of forecast days. Hourly breakdowns include wave height in metres, wave period in seconds, and wave direction in degrees.

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "days": {
       "type": "integer",
       "default": 2,
       "description": "Forecast days 1-7"
      },
      "port": {
       "type": "string",
       "description": "Preset Mediterranean port name (e.g. marseille, ajaccio, genoa)"
      },
      "latitude": {
       "type": "number",
       "description": "Marine point latitude (if no port given)"
      },
      "longitude": {
       "type": "number",
       "description": "Marine point longitude (if no port given)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "source": "Open-Meteo Marine (wave models ECMWF/MeteoFrance/DWD, CC-BY 4.0)",
  "summary": {
   "first_hours_wave_m": [
    0.38,
    0.4,
    0.44,
    0.5,
    0.54,
    0.58
   ],
   "max_wave_height_m_24h": 0.62,
   "max_wave_height_m_all": 0.88
  },
  "location": {
   "port": "marseille",
   "latitude": 43.25,
   "longitude": 5.375
  },
  "hourly_units": {
   "wave_height": "m",
   "wave_period": "s",
   "wave_direction": "°"
  },
  "forecast_days": 2
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/greeneris-sea-state-marine-weather-forecast-7649e3ca/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from data.greeneris.io](https://www.zero.xyz/host/data.greeneris.io/llms.txt)