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
“In the JSON metadata prompt, on the 5-versus-7 question, a single field — priority, set to 5 — dominated the steering, with an effective count of about 4 out of 12 slots.”Episode 243 — How a Hundred Meaningless Word Choices Add Up to Flip a Model's Answer