GET /v1/meta/fields

curl --request GET \
  --url https://api.example.com/v1/meta/fields

curl --request GET \
  --url https://api.example.com/v1/meta/fields

{
  "fields": [
    {
      "derivation": null,
      "description": "Ground elevation above the NAVD88 vertical datum at the queried point. Sourced from the USGS 3DEP 1/3 arc-second seamless DEM (~10m), with the USGS EPQS dynamic service as a coverage fallback.",
      "interpretation_hints": "Below 10m within 5km of the coast \u2192 storm-surge exposure relevant. Above 3000m \u2192 alpine permitting, snow loads. Combine with coast_distance_m and within_floodplain_polygon for flood-zone reasoning.",
      "layer": "terrain",
      "lifecycle": "stable",
      "name": "elevation",
      "null_meaning": null,
      "nullable": false,
      "presets": [
        "terrain",
        "flood_risk",
        "wildfire_underwrite",
        "site_selection",
        "wind_siting"
      ],
      "source": "USGS_3DEP",
      "source_url": "https://www.usgs.gov/3d-elevation-program",
      "ttl_seconds": 31536000,
      "type": "float",
      "unit": "meters"
    }
    /* ...295 more fields, ordered by layer */
  ],
  "presets": {
    "terrain": ["elevation", "slope_degrees", "aspect_cardinal", "coast_distance_m", "soil_drainage_class", "bedrock_depth_cm"],
    "flood_risk": ["elevation", "coast

import httpx, time

BASE = "https://api.mireye.com"

class CatalogClient:
    def __init__(self):
        self._etag: str | None = None
        self._catalog: dict | None = None
        self._fetched_at: float = 0.0

    async def get(self) -> dict:
        # Refresh at most once an hour, even if our cache lies.
        if self._catalog and time.time() - self._fetched_at < 3600:
            return self._catalog

        headers = {}
        if self._etag:
            headers["If-None-Match"] = self._etag

        async with httpx.AsyncClient() as c:
            r = await c.get(f"{BASE}/v1/meta/fields", headers=headers)

        if r.status_code == 304:
            self._fetched_at = time.time()
            return self._catalog  # unchanged

        r.raise_for_status()
        self._etag = r.headers["ETag"]
        self._catalog = r.json()
        self._fetched_at = time.time()
        return self._catalog

You are a geospatial data planner. Given a US coordinate and a natural-
language question, pick the catalog fields needed to answer it.

Available fields:
  elevation (terrain, float, meters) — Ground elevation above NAVD88...
    Hint: Use this when the caller asks about elevation...
    Presets: terrain, flood_risk, site_selection, wildfire_underwrite
  slope_degrees (terrain, float, degrees) — Slope at the coordinate...
    Hint: Spread potential for wildfire; higher = faster spread...
  /* ... */

Presets (use one of these instead of listing fields if it fits):
  flood_risk: elevation, coast_distance_m, within_floodplain_polygon, ...
  /* ... */