Context Free Grammar Cfg Constrained Generation

via “context-free grammar (cfg) constrained generation”

Structured text generation — guarantees LLM outputs match JSON schemas or grammars.

Unique: Integrates CFG parsing into the generation loop using an Earley parser to compute valid next tokens, enabling generation of syntactically valid code and DSL expressions without post-processing.

vs others: More expressive than regex constraints (supports nested structures and recursion) while remaining faster than post-hoc validation or rejection sampling.