Smart Contract LangChain Advisor integrates large language models via the LangChain framework to audit and improve Ethereum smart contracts. It performs static and semantic analysis on Solidity source code, identifying security issues like reentrancy, integer overflows, and access control flaws. The agent assesses gas consumption patterns and recommends optimizations to reduce transaction costs. It generates human-readable audit reports with prioritized findings and suggested code modifications. Developers can iteratively query the agent for explanations or deeper analysis of specific contract functions. By embedding into CI/CD pipelines, it continuously monitors code changes, ensuring high standards of security, performance, and compliance with best practices.