LangChain Chains Skill

Capabilities

• Compose LangChain chains using LCEL (LangChain Expression Language)
• Implement sequential chain patterns
• Design router chains for conditional logic
• Create parallel execution chains
• Handle chain fallbacks and retries
• Implement streaming chains

Target Processes

• dialogue-flow-design
• chatbot-design-implementation

Implementation Details

Chain Patterns

1. LCEL Pipelines: Modern composition with | operator
2. SequentialChain: Linear chain execution (legacy)
3. RouterChain: Conditional routing based on input
4. RunnableParallel: Parallel execution branches
5. RunnableBranch: Conditional branching

Configuration Options

• Input/output key mapping
• Error handling strategies
• Retry configuration
• Streaming settings
• Batch processing options

Best Practices

• Use LCEL for new implementations
• Implement proper input/output schemas
• Add fallback chains for resilience
• Use streaming for long operations

Dependencies

• langchain-core
• langchain