Kb-Bridge is an intelligent Model Context Protocol (MCP) server engineered to significantly enhance knowledge base search and retrieval. It features an extensible architecture that supports multiple retrieval backend providers, ensuring flexibility across various data sources. The server offers a comprehensive suite of search methods, including hybrid, semantic, keyword, and full-text search, alongside advanced functionalities like automatic answer quality evaluation and refinement through its reflection system, and the application of custom, domain-specific instructions to queries. It exposes a range of specialized tools, such as an `assistant` for intelligent answer extraction, a `retriever` for diverse search methods, and utilities for file discovery and keyword generation, making it a powerful solution for efficient information access and management within complex knowledge bases.