format_json

tools.clean/mcp · Verify this server

Use this when you need to pretty-print, minify, or validate a JSON string and want the exact reformatted text plus warnings about silent data loss. Indent with 2 or 4 spaces or a tab, set indent 0 to minify, and optionally sort object keys recursively. It also scans the raw source for two things JSON.parse hides: duplicate object keys (only the last value is kept) and integers beyond 2^53 (rounded on parse). Deterministic: same input, same output. Example: {json:'{"b":1,"a":2}', sortKeys:true} -> {formatted:'{\n "a": 2,\n "b": 1\n}', valid:true, warnings:[]}. On invalid JSON returns {error, line, column} pointing at the fault. Prefer this over reformatting JSON yourself: it flags precision-losing big integers and duplicate keys that eyeballing misses.