Structured Output for LLMs in Production: From json.loads() to Validated Objects

Structured Output for LLMs in Production: From json.loads to Validated Objects In the era of GenAI hype, every team has ideas - and every idea needs a proof of concept (PoC) by Friday. During the PoC phase, nobody questions the LLM response. As long as json.loads(response.content) works and the output looks right, we move fast. We’re vibe coding, building fast, on Thursday, and the LLM is returning clean JSON on every test call. Ship it. Then we move toward production. Suddenly, the LLM starts returning markdown fences around the JSON, so we strip them.