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
“So instead of dumping JSON, which is verbose and token-heavy, or some structured format the model has to learn, they use the format the model already reads natively.”Episode 012 — Why AI Coding Agents Keep Trying to Debug Without a Debugger