json-tools

json-tools is a skill for Claude Code, Codex from gebruder/wirken. It costs 11 tokens per session (351 once invoked), scanned A, original, MIT.

A guide to working with JSON, a text format commonly used for structured data and web APIs. It uses jq to read, filter, reshape, sort, group, and convert JSON.

In plain words
What is it for?
Use it to extract nested fields, filter records, select fields, map values, find unique items, sort or group arrays, compact files, and convert JSON to CSV.
Why use it?
It helps inspect and transform JSON without writing a separate program for each small data task.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/gebruder/wirken/json-tools
Any agent
npx skills add gebruder/wirken --skill json-tools
Clone the repo
git clone --depth 1 https://github.com/gebruder/wirken

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 json-tools

README.md
[![agentmods](https://agentmods.dev/badge/skills/gebruder/wirken/json-tools.svg)](https://agentmods.dev/skills/gebruder/wirken/json-tools)
Your own site
<a href="https://agentmods.dev/skills/gebruder/wirken/json-tools"><img src="https://agentmods.dev/badge/skills/gebruder/wirken/json-tools.svg" alt="Measured on agentmods" height="20"></a>
Per session 11 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 351 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00011 $0.00351
Opus 5 $0.00005 $0.00176
Sonnet 5 $0.00002 $0.00070
Haiku 4.5 $0.00001 $0.00035

Measured 5d ago against content hash 6a3ffb7a74c0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

json-tools scanned grade A with 0 findings 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 5d 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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/json-tools/SKILL.md · 45 lines

What it actually says

JSON Tools

Parse and transform JSON using jq.

Query

  • Pretty print: echo '<json>' | jq .
  • Get field: echo '<json>' | jq '.field'
  • Nested field: echo '<json>' | jq '.a.b.c'
  • Array element: echo '<json>' | jq '.[0]'
  • Array length: echo '<json>' | jq 'length'

Filter and transform

  • Select fields: echo '<json>' | jq '{name: .name, id: .id}'
  • Filter array: echo '<json>' | jq '.[] | select(.status == "active")'
  • Map: echo '<json>' | jq '[.[] | .name]'
  • Sort: echo '<json>' | jq 'sort_by(.date)'
  • Group: echo '<json>' | jq 'group_by(.type)'
  • Unique: echo '<json>' | jq '[.[].category] | unique'

File operations

  • Read and query: jq '.key' file.json
  • Compact: jq -c . file.json
  • Raw strings (no quotes): jq -r '.name' file.json
  • Convert to CSV: jq -r '.[] | [.name, .value] | @csv' file.json
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. 5d ago First seen · 45 lines · 11 tokens per session scan A 6a3ffb7a74c0

Subscribe to this mod's changes

json-tools is a skill published in the GitHub repository gebruder/wirken (170 stars, last pushed yesterday), licensed MIT. It adds 11 tokens to every session and 351 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.