Suppress duplicate YOLO tile detections

docs/AI_PIPELINES.md

@@ -110,6 +110,7 @@ Environment variables:
 - `YOLO_IMAGE_SIZE`
 - `YOLO_MAX_TILES`
 - `YOLO_MAX_DETECTIONS`
+- `YOLO_DUPLICATE_IOU_THRESHOLD`
 - `YOLO_BATCH_SIZE`
 
 `YOLO_MAX_DETECTIONS` is forwarded to Ultralytics as `max_det` for each
@@ -119,6 +120,15 @@ the upstream default would cap recall before QA/QC begins. Operators may lower
 the value for small rasters or raise it for dense urban tiles after reviewing
 runtime and false-positive behavior.
 
+After YOLO boxes are georeferenced, configured-YOLO runs apply a GeoIntel
+cross-tile duplicate suppression pass before persistence. Candidates are grouped
+by canonical class and sorted by confidence; lower-confidence same-class
+candidates with EPSG:4326 geometry IoU greater than or equal to
+`YOLO_DUPLICATE_IOU_THRESHOLD` are suppressed. The default is `0.5`; set it to
+`0` to disable this post-processing for operator debugging. Run summaries record
+raw, persisted and suppressed detection counts so calibration evidence remains
+auditable.
+
 ### Local model asset catalog
 
 GeoIntel can list local runtime model files mounted into the backend model
@@ -205,6 +215,9 @@ persisted project quality-check list to build `calibration_summary.json`.
 Results are honest QA/QC evidence from persisted detections and persisted
 reference `vector_features`; no demo detections, live provider fetches or model
 downloads are introduced by the calibration tool.
+Summaries include raw detection candidate count, persisted detection count and
+suppressed duplicate count so operators can distinguish model output volume from
+GeoIntel post-processing.
 
 For model/tile/threshold selection, use the quality matrix wrapper: