Definition
Plain language
A simple text format computers use to exchange structured data.
As stated in the literature
JavaScript Object Notation — a human-readable, language-agnostic data interchange format using key-value maps and ordered lists.
Why it matters: It's the lingua franca for structured tool calls and responses, so essentially every modern agent framework speaks JSON at its boundaries.
For example, an API might return {"user": "alice", "items": [1, 2, 3]} as a JSON response to a request.
Heard on the show
“" Force the output into clean JSON.”Episode 191 — How One Researcher Beat GPT-5.2 and Gemini 3 by Judging Their Answers, Not Improving Them