json-patcher

The chief cook and bottle washer of json patching

Overview

json-patcher is a tool that processes JSON files and generates patches, fixes, and changelogs. This project helps manage and track changes between different JSON files.

Features

• Generate patches between JSON files
• Generate human-readable descriptions from patch files
• Apply patch files to JSON files
• Append generated descriptions to a changelog
• Emit JSON output for automation with --json

LLM Compatibility

The describe command currently expects an OpenAI-compatible Chat Completions API.

• Expected request shape: {"model": "...", "messages": [...]}
• Expected response shape: choices[0].message.content

This works with OpenAI and providers/proxies exposing an OpenAI-compatible Chat Completions endpoint. Anthropic’s native Messages API is not directly supported.

Installation

bbin install io.github.200ok-ch/json-patcher

Usage

Examples

json-patcher diff old.json new.json --out changes.patch
json-patcher describe changes.patch --append CHANGELOG.md
json-patcher apply old.json fix.patch --out old-fix.json
json-patcher diff old.json new.json --json

Requirements

• Babashka
• jsondiff/jsonpatch
• OpenAI API Key (optional)

Examples

./json_patcher.bb diff li-20260302T092642Z-v1.json li-20260302T092703Z-v2.json --out patch-v1-v2.json --json