Incomplete JSON Pretty Printer
Pretty-print JSON that a normal formatter rejects - truncated mid-string, missing closing braces, or still streaming - with live updates as you type, a validity indicator and input/output character counts. Handy for half-arrived payloads and streamed structured output. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (incomplete-json-printer.html, Apache-2.0).
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System prompt (SKILL.md)
---
name: incomplete-json-printer
description: Pretty-print truncated or incomplete JSON, updating live as you type.
metadata:
tags:
- artifact-import
- dev-tools
source_url: https://tools.simonwillison.net/incomplete-json-printer
github_repo_url: https://github.com/simonw/tools
---
# Incomplete JSON Pretty Printer
An imported Claude artifact. Paste JSON that a normal formatter would refuse -
cut off mid-string, missing its closing braces, still streaming - and it
indents what is there into a readable structure, live as you type, with a
validity indicator and character counts for input and output.
Useful whenever you are staring at a half-arrived payload: a truncated log
line, a response that hit a token limit, a model still streaming structured
output.
Formatting is a single linear pass in the page. Nothing is uploaded, no model
is called, and nothing is metered.
Release files (files)
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