data_dictionary

What weather data exists for a topic, and which tool serves it. Free, no credits.

Call this FIRST for exploratory questions ("do you have hail data?",
"how far back does rainfall go?"). Three modes:

1. SEARCH (query given — the primary mode): searches every variable/product
   across all datasets (station, gridded 15km, climate normals, precipitation,
   severe weather, hurricanes, risk scores, forecast, ...). Returns compact
   routing entries {variable, dataset, units, tool, one_line} — call the
   named tool next. detail='full' adds resolution, coverage, and caveats.
2. LOOKUP (variable_names given): definition, units, and default flag for
   exact API variable names (e.g. 'surfaceTemperature'). Not a search —
   names must match exactly.
3. LIST (neither given): dataset='station'|'gridded'|'climate_normals'
   returns that dataset's field packages, valid fields, and supported
   intervals — call before station_historical_data, station_climate_normals,
   or gridded_history_15km to choose the 'fields' parameter (if the intent
   doesn't map to a package, use fields='all' in the data call).
   dataset='all' (default) returns the compact dataset catalog.

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "data_dictionary",
    "arguments": {
      "dataset": "all",
      "detail": "compact",
      "top_k": 5,
      "content_mode": "text"
    }
  }
}

{
  "name": "data_dictionary",
  "arguments": {
    "dataset": "all",
    "detail": "compact",
    "top_k": 5,
    "content_mode": "text"
  }
}