Remote built a Code Execution Agent using LangChain and LangGraph to automate customer data migrations during onboarding. The system separates LLM reasoning from code execution: models decide what transformations to perform, while Python code in a WebAssembly sandbox handles actual data processing. This hybrid approach bypasses context window limitations and hallucination risks by keeping large datasets outside the LLM's context. The agent transforms diverse HR and payroll data formats (CSV, Excel, SQL exports) into standardized JSON schemas, reducing migration time from days to hours while maintaining accuracy and auditability for compliance-critical operations.
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The Challenge: Context windows and hallucinationsThe Solution: Let the models reason, let code executeWhy LangChain and LangGraphResults and impactLessons learnedWhat’s nextFinal thoughtsSort: