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+# Changelog
+
+## [Unreleased]
+
+### Chat Backend (`chatbot_backend.py`)
+- Removed the `classify_input` function that differentiated between conversation and hybrid modes.
+- The model now always executes the full RAG pipeline to generate a direct response for queries.
+- Updated chatbot to include modality details in model recommendations.
+- **Old Approach:** Hybrid chatbot that could do both casual conversation and technical search.
+- **New Approach:** Specialized ML recommendation system that treats every query as a technical search request.
+
+### Hugging2SQL (`hugging2sql.py`)
+**Purpose:** This script crawls the Hugging Face API to collect machine learning models and stores it in a SQLite database for knowledge graph construction.
+- Switched to official Hugging Face Hub API (replaced direct HTTP requests with the library).
+- Implemented data quality filtering → only models with more than 15 downloads are included.
+- Database expansion: model repository increased from ~25,000 to ~32,000 models.
+
+### Model Status Check Script
+**Purpose:** This script validates the usability of a model present in the database by testing if it can be loaded and used properly. 
+- Created a script that downloads, loads, and executes test predictions on each model to verify usability.
+- Enhanced database schema with new columns: `health_status`, `last_checked`, and `health_error`.
+- `health_error` keeps records of error messages for debugging.
+- Current progress: Model validation testing is ongoing across the entire model library; database will be updated as validation completes.
+
+### Model Card Extraction Script
+- Now uses Hugging Face authentication to access both private and public models.
+
+### Semantic Search (`semantic_search.py`)
+- (No changes recorded yet)
+
+### DB → Annoy (`db2annoy.py`)
+- (No changes recorded yet)
+
+### DB → Neo4j (`db2neo4j.py`)
+- (No changes recorded yet)
+
+### Chatbot Frontend (`chatbot_frontend.html`)
+- (No changes recorded yet)