Technique

JSON Mode

API mode that forces a model to emit syntactically-valid JSON output.

Definition

JSON mode constrains decoding to produce valid JSON, eliminating the need for retry parsing. Modern providers extend this to schema-constrained 'structured outputs' where the JSON must additionally match a provided JSON Schema, guaranteeing parseability.

Common use cases

  • API integrations
  • ETL
  • Database ingestion

Related terms

    JSON Mode — AI Glossary | Railwail