NWS Weather Forecast

Fetch public National Weather Service forecast evidence through runx HTTP.

This is a branded provider skill for the canonical weather-forecast verb. It uses the governed HTTP front, not an ad hoc client: the receipt records the NWS endpoint, response status, graph step receipts, and the exact authority surface. No API key is required. The default runner fetches the actual NWS gridpoint forecast; the locate runner discovers the gridpoint for a latitude/longitude.

What this skill does

nws-weather-forecast makes read-only calls to api.weather.gov. The locate runner calls /points/{lat},{lon} to discover gridId, gridX, gridY, and forecast URLs. The default forecast runner calls /gridpoints/{office}/{grid_x},{grid_y}/forecast to fetch forecast periods. The output is provider evidence; use weather-forecast when an agent needs to normalize that evidence for a planning decision.

When to use this skill

• You need real public weather evidence with no credentials.
• A graph needs to prove a weather data read went through runx's governed HTTP path.
• You have an NWS office/gridpoint and need the current public forecast.
• You have latitude and longitude in the United States and need the NWS gridpoint before running the forecast path.

When not to use this skill

• For locations outside NWS coverage. Return needs_input with the coverage limitation.
• For emergency, medical, aviation, maritime, evacuation, or life-safety decisions.
• To notify users, reschedule events, deploy changes, or mutate operations based on weather. Those actions need their own authority gate.
• To call private networks, untrusted hosts, or non-NWS endpoints.

Procedure

1. If the caller has only coordinates, run locate with lat and lon.
2. Extract gridId, gridX, and gridY from the sealed locate output.
3. Run the default forecast runner with office, grid_x, and grid_y.
4. Confirm the HTTP status is 2xx and the response contains forecast periods.
5. Preserve the NWS source URL, generated timestamp, gridpoint, and receipt refs.
6. If an agent needs planning prose, pass the provider evidence to weather-forecast. Do not invent guidance inside this provider fetch.
7. Return needs_input for malformed coordinates or gridpoints; return needs_more_evidence for NWS outages, missing periods, or stale data.

Edge cases and stop conditions

• Invalid coordinates: return needs_input; NWS point lookup requires decimal latitude and longitude.
• Unsupported location: return needs_input; NWS coverage is not global.
• Provider outage or non-2xx response: return needs_more_evidence and preserve the HTTP status in the receipt.
• Missing forecast periods: return needs_more_evidence; do not summarize a forecast that is not present.
• Life-safety use: return refused and direct the user to official weather or emergency channels.
• Action requested from weather: stop at provider evidence and require the downstream action skill with its own gate and receipt.

Output schema

decision: ready | needs_input | needs_more_evidence | refused
canonical_skill: runx/weather-forecast
runtime_path: http
provider: national-weather-service
provider_evidence:
  endpoint: string
  http_status: string
  gridpoint:
    office: string
    grid_x: string
    grid_y: string
  generated_at: string
  forecast_periods: array
receipt_refs: array
stop_conditions: array

Worked example

1. Run locate for 38.8894,-77.0352.
2. The sealed NWS points response returns gridId: LWX, gridX: 97, gridY: 71, and a forecast URL.
3. Run the default forecast runner with office: LWX, grid_x: "97", grid_y: "71".
4. Use the sealed forecast JSON as forecast_evidence for weather-forecast when a downstream agent needs a planning packet.

Inputs

• office (default runner, required): NWS office id such as LWX.
• grid_x (default runner, required): NWS grid X coordinate.
• grid_y (default runner, required): NWS grid Y coordinate.
• lat (locate runner, required): decimal latitude for point lookup.
• lon (locate runner, required): decimal longitude for point lookup.