json-difference: Instructions file for Codex

AGENTS.md

json-difference AGENTS.md is an instructions file for Codex, OpenCode from lukascivil/json-difference. It costs 337 tokens per session, scanned A, original, MIT.

A shorter guide for working in an Nx workspace, where multiple applications and libraries are managed together from one repository.

In plain words
What is it for?
It helps run Nx builds, tests, and other tasks, and explains when to use Nx documentation or the project-generation workflow.
Why use it?
It prevents guessed command options and encourages using the workspace's project-aware commands and documentation.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md.

This is lukascivil/json-difference's own configuration. It tells Codex and OpenCode how to work on json-difference itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything json-difference configures →

Reuse

Borrowing it

Nothing to install: this file belongs to lukascivil/json-difference. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/lukascivil/json-difference/master/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/lukascivil/json-difference

Made for: Codex, OpenCode.

Wrote this? Show the measurements

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README.md
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Your own site
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Per session 337 This file is loaded in full into every session.
When invoked 337 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00337 $0.00337
Opus 5.5 $0.00135 $0.00135
Sonnet 5.5 $0.00067 $0.00067
Haiku 4.5 $0.00034 $0.00034

Measured 1mo ago against content hash 45964d717194, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

json-difference AGENTS.md 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 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.

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.

Origin

Copies of this mod

5 near-identical copies found in the catalogue:

AGENTS.md · 24 lines

What it actually says

General Guidelines for working with Nx

  • For navigating/exploring the workspace, invoke the nx-workspace skill first - it has patterns for querying projects, targets, and dependencies
  • When running tasks (for example build, lint, test, e2e, etc.), always prefer running the task through nx (i.e. nx run, nx run-many, nx affected) instead of using the underlying tooling directly
  • Prefix nx commands with the workspace's package manager (e.g., pnpm nx build, npm exec nx test) - avoids using globally installed CLI
  • You have access to the Nx MCP server and its tools, use them to help the user
  • For Nx plugin best practices, check node_modules/@nx/<plugin>/PLUGIN.md. Not all plugins have this file - proceed without it if unavailable.
  • NEVER guess CLI flags - always check nx_docs or --help first when unsure

Scaffolding & Generators

  • For scaffolding tasks (creating apps, libs, project structure, setup), ALWAYS invoke the nx-generate skill FIRST before exploring or calling MCP tools

When to use nx_docs

  • USE for: advanced config options, unfamiliar flags, migration guides, plugin configuration, edge cases
  • DON'T USE for: basic generator syntax (nx g @nx/react:app), standard commands, things you already know
  • The nx-generate skill handles generator discovery internally - don't call nx_docs just to look up generator syntax
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 · 24 lines · 337 tokens per session scan A 45964d717194

Subscribe to this mod's changes

json-difference AGENTS.md is an instructions file published in the GitHub repository lukascivil/json-difference (58 stars, last pushed 2mo ago), licensed MIT. It adds 337 tokens to every session, about $0.0013 per session on Opus 5.5. 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.

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