Section 08
Tips & best practices
Practical advice for preparing files and getting the best results out of TerraQuery.
File preparation
- GeoJSON CRS: Use WGS84 (EPSG:4326). Most drone processing software exports this by default.
- Shapefile ZIPs: Pack all components (
.shp,.dbf,.shx,.prj) into a single ZIP. TerraQuery converts to GeoJSON automatically, including CRS reprojection if needed. - TIFF format: Cloud-Optimized GeoTIFF (COG) is recommended. Non-COG TIFFs work but may be slower to tile.
- Band order: For multispectral TIFFs, band roles are detected automatically — no need to rearrange bands.
Getting better chat results
- Ask specific questions — "How many solar panels are defective in the northwest zone?" beats "What's wrong?"
- Reference object types from your data — if your classes are
Solar_Panelandtest_1_defects, use those terms. - Ask for summaries: "Give me a summary of the site health" triggers aggregation mode which computes totals across all features.
- For index requests, be explicit: "Show NDVI using the default bands" or "Show NDVI using band 8 as NIR and band 4 as Red."
Processing time
| File type | Expected time |
|---|---|
| GeoJSON < 500 features | 30–60 seconds |
| GeoJSON 500–2000 features | 1–4 minutes |
| GeoJSON > 2000 features | 5–15 minutes |
| TIFF upload (any size) | Depends on file size and connection |
Processing time scales with feature count because each feature is individually embedded via the OpenAI API.
Map performance
- Map tiles are computed on demand. The first load of an index on a large TIFF may take 1–2 seconds per tile.
- Tiles are cached per zoom level and index. Subsequent views of the same area load instantly.
- Switching between indices forces a full tile reload (cache is intentionally bypassed so you always see the correct index).
Index not available?
If an index button is greyed out or missing, your TIFF doesn't have the required bands:
- NDVI, SAVI, EVI require a NIR band (typically a multispectral camera)
- NDRE requires both NIR and RedEdge bands
- RGB indices (VARI, ExG, GLI, NGRDI) are always available
You can override band detection by asking the agent: "Use band 5 as NIR and band 3 as Red for NDVI". This forces the renderer to use those exact band numbers regardless of auto-detection.