Update docs metadata (#3781)

docs/reference/engine/exporter.md

@@ -1,3 +1,8 @@
+---
+description: Explore the exporter functionality of Ultralytics. Learn about exporting formats, iOSDetectModel, and try exporting with examples.
+keywords: Ultralytics, Exporter, iOSDetectModel, Export Formats, Try export
+---
+
 ## Exporter
 ---
 ### ::: ultralytics.engine.exporter.Exporter
@@ -26,4 +31,4 @@
 ## export
 ---
 ### ::: ultralytics.engine.exporter.export
-<br><br>
+<br><br>

docs/reference/engine/model.md

@@ -1,4 +1,9 @@
+---
+description: Explore the detailed guide on using the Ultralytics YOLO Engine Model. Learn better ways to implement, train and evaluate YOLO models.
+keywords: Ultralytics, YOLO, engine model, documentation, guide, implementation, training, evaluation
+---
+
 ## YOLO
 ---
 ### ::: ultralytics.engine.model.YOLO
-<br><br>
+<br><br>

docs/reference/engine/predictor.md

@@ -1,4 +1,9 @@
+---
+description: Learn about Ultralytics BasePredictor, an essential component of our engine that serves as the foundation for all prediction operations.
+keywords: Ultralytics, BasePredictor, YOLO, prediction, engine
+---
+
 ## BasePredictor
 ---
 ### ::: ultralytics.engine.predictor.BasePredictor
-<br><br>
+<br><br>

docs/reference/engine/results.md

@@ -1,3 +1,8 @@
+---
+description: Master Ultralytics engine results including base tensors, boxes, and keypoints with our thorough documentation.
+keywords: Ultralytics, engine, results, base tensor, boxes, keypoints
+---
+
 ## BaseTensor
 ---
 ### ::: ultralytics.engine.results.BaseTensor
@@ -26,4 +31,4 @@
 ## Probs
 ---
 ### ::: ultralytics.engine.results.Probs
-<br><br>
+<br><br>

docs/reference/engine/trainer.md

@@ -1,4 +1,9 @@
+---
+description: Learn about the BaseTrainer class in the Ultralytics library. From training control, customization to advanced usage.
+keywords: Ultralytics, BaseTrainer, Machine Learning, Training Control, Python library
+---
+
 ## BaseTrainer
 ---
 ### ::: ultralytics.engine.trainer.BaseTrainer
-<br><br>
+<br><br>

docs/reference/engine/validator.md

@@ -1,4 +1,9 @@
+---
+description: Learn about the Ultralytics BaseValidator module. Understand its principles, uses, and how it interacts with other components.
+keywords: Ultralytics, BaseValidator, Ultralytics engine, module, components
+---
+
 ## BaseValidator
 ---
 ### ::: ultralytics.engine.validator.BaseValidator
-<br><br>
+<br><br>