response-parser

Covers the non-obvious failure modes and patterns for parsing structured output from LLM responses. Assumes basic JSON/fetch knowledge.

1. Fence Extraction — What Actually Goes Wrong

Models don't always produce clean ```json ... ```. Real-world variants:

```JSON          ← uppercase
``` json         ← space after backticks
```json\n\n{     ← double newline before content
{                ← no fence at all (common with strong system prompts)
Here's your JSON:\n```json   ← preamble before fence

Extraction regex that handles all of these: