jzen

name	jzen
description	Minimal-token JSON editor for AI agents. Use jzen to read/write JSON configs with minimal context usage. Triggers: edit JSON, modify config, update settings, read config values, repair JSON.

Jzen — Agent-Optimized JSON Editor

Jzen reads/writes JSON with minimal token output. Install: cargo install jzen or download from https://github.com/caoergou/jzen

Core Commands

Command	Use For
jzen get .key file.json	Read single value
jzen set .key '"value"' file.json	Set value (JSON value, note quotes)
jzen del .key file.json	Delete key
jzen add .array '"item"' file.json	Append to array
jzen patch '[{"op":"replace","path":".key","value":1}]' file.json	Batch operations
jzen fix file.json	Auto-repair JSON errors
jzen schema file.json	Get structure (no values)
jzen tree file.json	Visual tree view

Path Syntax

.key              # object field
.nested.key      # deep path
.array[0]        # array index (0-based)
.array[-1]       # last element

Agent Examples

# Read config structure (type-only, minimal tokens)
jzen schema ~/.claude/settings.json

# Check if key exists (exit code 0=exists, 2=not found)
jzen exists .mcpServers.github ~/.claude/settings.json

# Get single value
jzen get .mcpServers.github.command ~/.claude/settings.json

# Set value (note: string values need extra quotes)
jzen set .mcpServers.github.env.TOKEN '"ghp_xxxx"' ~/.claude/settings.json

# Batch update in one call
jzen patch '[
  {"op": "replace", "path": ".defaultMode", "value": "Command"},
  {"op": "add", "path": ".mcpServers.newServer.enabled", "value": true}
]' ~/.claude/settings.json

# Fix JSON errors (trailing commas, comments, etc)
jzen fix --strip-comments broken.json

Output Behavior

• Strings: Raw output (no quotes) — safe for shell
• Objects/Arrays: Pretty-printed JSON
• Success: No output or single word (ok, deleted)
• Errors: stderr with message, exit code 1-3

Exit Codes

Code	Meaning
0	Success
1	Error
2	Path not found
3	Type mismatch

Tips

• Use patch for multiple changes — single round-trip
• Use schema to understand structure without reading values
• Use --json flag for machine-parseable output
• File argument can be before or after command: jzen file.json get .key or jzen get .key file.json