zjson

zjson is a skill for Claude Code, Codex from AdamBien/airails. It costs 109 tokens per session (1,492 once invoked), scanned A, original, MIT.

A small set of Java source files for reading and creating JSON, a common text format for structured data. You copy the files into the project instead of adding a Maven or Gradle library dependency.

In plain words
What is it for?
Use it in Java command-line tools or other projects that need to parse JSON input or build JSON output without installing a package manager dependency.
Why use it?
It lets a Java project handle JSON while remaining dependency-free. It is intended for Java 21 or newer.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it in Java command-line tools or other projects that need to parse JSON input or build JSON output without installing a package manager dependency.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/adambien/airails/zjson
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add AdamBien/airails --skill zjson
Clone the repo
git clone --depth 1 https://github.com/AdamBien/airails

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for zjson

README.md
[![agentmods](https://agentmods.dev/badge/skills/adambien/airails/zjson/github.svg)](https://agentmods.dev/skills/adambien/airails/zjson)
Your own site
<a href="https://agentmods.dev/skills/adambien/airails/zjson"><img src="https://agentmods.dev/badge/skills/adambien/airails/zjson/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for zjson

Your own site · 80×15
<a href="https://agentmods.dev/skills/adambien/airails/zjson"><img src="https://agentmods.dev/badge/skills/adambien/airails/zjson.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 109 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,492 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00109 $0.01492
Opus 5.5 $0.00044 $0.00597
Sonnet 5.5 $0.00022 $0.00298
Haiku 4.5 $0.00011 $0.00149

Measured 1mo ago against content hash 7276ce551d1a, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

zjson scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

Copy the three files from GitHub, preserving the `org/json` path. This is the canonical method — it needs only `curl` and works on any machine, with no local checkout or extra tooling:
java/zjson/SKILL.md · 127 lines

How it starts

The opening of the file, as written. The whole thing — 127 lines — stays where its author put it; the contents beside it link to each section on GitHub.

zjson — JSON via Source Copy

Add JSON parsing and generation to a Java project by copying the org.json source files in — no Maven or Gradle dependency.

What is zjson

A Java 25, zero-dependency fork of the org.json reference implementation, trimmed to three classes:

  • JSONObject — JSON object: key/value map with typed accessors

  • JSONArray — JSON array: ordered values, Iterable<Object>

  • JSONTokener — the parser both classes delegate to

  • Package: org.json

  • Source: https://github.com/AdamBien/z-JSON-java (src/main/java/org/json)

  • Requires: Java 21+ (developed against Java 25)

Not included in this fork: JSONStringer, JSONWriter, XML/CDL/HTTP/Cookie conversion. Use JSONObject and JSONArray for building output.

Source Integration

Copy the org/json package into the project's source root — keep the package org.json; declarations unchanged. Unlike single-class utilities, the package is not repackaged; org.json stays as-is and is imported with import org.json.*;.

Copy the three files from GitHub, preserving the org/json path. This is the canonical method — it needs only curl and works on any machine, with no local checkout or extra tooling:

for f in JSONObject JSONArray JSONTokener; do
  curl -sf "https://raw.githubusercontent.com/AdamBien/z-JSON-java/main/src/main/java/org/json/$f.java" \
    -o "src/main/java/org/json/$f.java" --create-dirs
done

For a single-file zb/CLI project whose source root is the project root, drop the src/main/java/ prefix and copy into org/json/ directly. After copying, build normally (e.g. /zb). The three files compile alongside application code with no further configuration.

Optional local shortcut: if a z-JSON-java checkout and the zjsoncp script are present on the machine, running zjsoncp from the source root copies the same org/json package locally. This is a convenience only — the curl method above is the portable default.

API

Parsing

import org.json.*;

JSONObject obj = new JSONObject("""
    {"name":"Duke","age":29,"tags":["java","jvm"],"active":true}
    """);

String name   = obj.getString("name");          // "Duke"
int age        = obj.getInt("age");              // 29
boolean active = obj.getBoolean("active");       // true
JSONArray tags = obj.getJSONArray("tags");       // ["java","jvm"]

JSONArray arr = new JSONArray("[1,2,3]");
int first = arr.getInt(0);                        // 1

Read the full file on GitHub · 127 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 1mo ago First seen · 127 lines · 109 tokens per session scan A 7276ce551d1a

Subscribe to this mod's changes

zjson is a skill published in the GitHub repository AdamBien/airails (58 stars, last pushed 3d ago), licensed MIT. It adds 109 tokens to every session and 1,492 once invoked, about $0.0004 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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