# TASK-007: Implement Incremental Indexing
## Status: COMPLETE
## Description
Implement incremental indexing to improve performance for large codebases. Instead of re-indexing all files on startup, only process files that have been added, modified, or deleted since the last indexing operation.
## Implementation Details
- [x] Add file metadata tracking (hashes, modification times, sizes)
- [x] Implement efficient file change detection
- [x] Add incremental indexing mode (default) with full reindex option
- [x] Update MCP interface to expose reindexing controls
- [x] Add CLI option for forcing full reindex
- [x] Handle deleted files properly
## Technical Notes
The implementation uses the following approach:
1. **File Metadata Tracking**:
- Store file hashes, modification times, and sizes in state file
- Compute SHA-256 hash for text files (with size limit for performance)
- For large files, use size+mtime combination as a proxy for content hash
2. **Change Detection Algorithm**:
- On startup, scan all files in project directory
- Compare against previously indexed files to find:
- New files to add
- Modified files to update (based on hash/mtime/size)
- Deleted files to remove
- Only process files that need updating
3. **Performance Optimizations**:
- Skip hash computation for large files (>10MB)
- Process files in parallel with thread pool
- Early filtering of ignored files and directories
- Efficient state file management
4. **API Enhancements**:
- Added `trigger_reindex` MCP command to force reindexing
- Added `get_indexing_status` MCP command to check progress
- Added proper metadata handling in vector storage
5. **CLI Options**:
- Added `--force-reindex` flag to command line interface
- Incremental indexing is enabled by default
## Benefits
- Significantly faster startup times for large codebases
- Reduced system resource usage during indexing
- Better handling of large files
- More accurate change detection
- User control over indexing behavior
## Limitations
- File change detection outside the application requires file system events
- Large binary files still rely on mtime/size instead of content hash
- State file can grow large for repositories with many files
## Related Tasks
- TASK-006: Project Initialization Process
- TASK-018: Beta Release Preparation
## References
- [Qdrant Client Documentation](https://qdrant.github.io/qdrant/docs/reference/api/)
- [File Hashing Best Practices](https://en.wikipedia.org/wiki/Hash_function)