BAML Code Generation

Generate type-safe LLM extraction code. Use when creating structured outputs, classification, RAG, or agent workflows.

Golden Rules

• NEVER edit baml_client/ - 100% generated, overwritten on every baml-cli generate; check baml_src/generators.baml for output_type (python, typescript, ruby, go)
• ALWAYS edit baml_src/ - Source of truth for all BAML code
• Run baml-cli generate after changes - Regenerates typed client code for target language

Philosophy (TL;DR)

• Schema Is The Prompt - Define data models first, compiler injects types
• Types Over Strings - Use enums/classes/unions, not string parsing
• Fuzzy Parsing Is BAML's Job - BAML extracts valid JSON from messy LLM output
• Transpiler Not Library - Write .baml → generate native code (Python/TypeScript/Ruby/Go), no runtime dependency
• Test-Driven Prompting - Use VS Code playground or baml-cli test to iterate

Workflow