JSON (JavaScript Object Notation)
Also: json 格式 · json 檔案 · json file · javascript object notation
A lightweight data format in plain text that both humans and programs can read — the common language of AI tooling.
When you will meet it
The request you send an LLM API is JSON, the response is JSON, the tool calls a model returns are JSON, and most AI config files are JSON too. Its rules are few but utterly unforgiving: one missing quote or trailing comma rejects the whole payload, and the error often hands you only a line and column to hunt with.
An analogy
Like a fill-in form: fields (keys) paired with contents (values) in a fixed layout, so whoever receives it can process it mechanically. JSON is programming's most popular form template — simple enough that even a language model can fill it in reliably.
Minimal example
echo '{ "model": "demo", "temperature": 0.7, "tags": ["a", "b"] }' | python3 -m json.toolpython3 -m json.tool is JSON's X-ray machine: valid JSON comes back pretty-printed; broken JSON reports the line and column. Run any suspect config file or API payload through it before hunting by eye.
What people get wrong
- Single quotes, a comma after the last item, or comments — all everyday JavaScript, all banned in JSON. "Almost-JSON" config files are a beginner hot zone.
- Assuming a .json extension guarantees valid JSON inside. Hand-edited files pick up invisible characters, and some tools' "JSON" actually tolerates comments (JSONC). When in doubt, validate with a tool instead of your eyes.
Related terms
Next
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