nv-context: Instructions file for Codex

AGENTS.md

nv-context AGENTS.md is an instructions file for Codex, OpenCode from johnnichev/nv-context. It costs 905 tokens per session, scanned C, original, MIT.

Project instructions for nv-context, a context-engineering skill distributed as Markdown files. Context engineering means deciding which project information an AI coding agent should receive for a request.

In plain words
What is it for?
Installing nv-context, testing it in another project, checking its line count, and preserving its required confirmation and maturity rules.
Why use it?
They help keep the skill and its instruction files within the project's size and design limits.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: reads .claude/ paths; mentions CLAUDE.md; mentions AGENTS.md.

This is johnnichev/nv-context's own configuration. It tells Codex and OpenCode how to work on nv-context 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 nv-context configures →

Reuse

Borrowing it

Nothing to install: this file belongs to johnnichev/nv-context. 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/johnnichev/nv-context/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/johnnichev/nv-context

Made for: Codex, OpenCode.

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 nv-context AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/johnnichev/nv-context/agents-md/github.svg)](https://agentmods.dev/instructions/johnnichev/nv-context/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/johnnichev/nv-context/agents-md"><img src="https://agentmods.dev/badge/instructions/johnnichev/nv-context/agents-md/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 nv-context AGENTS.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/johnnichev/nv-context/agents-md"><img src="https://agentmods.dev/badge/instructions/johnnichev/nv-context/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 905 This file is loaded in full into every session.
When invoked 905 The same file — it is already loaded in full.
Security scan C 1 finding. 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 $0.00905 $0.00905
Opus 5.5 $0.00362 $0.00362
Sonnet 5.5 $0.00181 $0.00181
Haiku 4.5 $0.00090 $0.00090

Measured 1mo ago against content hash 8649114bef0a, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade C, and why

nv-context AGENTS.md scanned grade C 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.

Hidden instructionshighPrompt injection

Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.

<!-- CORRECT: Positive instruction (research-backed) -->
AGENTS.md · 79 lines

How it starts

The opening of the file, as written. The whole thing — 79 lines — stays where its author put it; the contents beside it link to each section on GitHub.

nv-context

Context engineering skill distribution. NOT an application -- this repo ships SKILL.md and supporting docs to ~/.claude/skills/nv-context/.

Commands

# Install skill globally (recommended)
npx skills add johnnichev/nv-context -g -y

# Install skill manually
mkdir -p ~/.claude/skills/nv-context && cp skills/nv-context/SKILL.md ~/.claude/skills/nv-context/

# Test skill works (open any project, then run)
/nv-context

# Verify SKILL.md line count (MUST stay under 500)
wc -l skills/nv-context/SKILL.md

Stack

  • Pure markdown skill -- no runtime, no dependencies, no build step
  • package.json exists for npm discoverability only (no scripts, no node_modules)
  • hooks/ contains reference examples users copy into their own repos, not hooks for this repo

Boundaries

Always

  • Run wc -l skills/nv-context/SKILL.md after any edit -- MUST be under 500 lines
  • Validate that SKILL.md Phase 0 still offers ONE confirmation (not a form)
  • Keep AGENTS.md under 200 lines, CLAUDE.md under 50 lines

Ask First

  • Changing the 8 Core Laws in SKILL.md (these are research-backed)
  • Modifying the L0-L6 maturity criteria or Hierarchy of Leverage scoring rubric
  • Adding new phases to SKILL.md (each phase costs ~30 lines of budget)
  • Changing install commands in README.md or docs/QUICKSTART.md

Never

  • NEVER modify files in research/logs/ -- these are completed research artifacts (484KB, 12 docs, 200+ sources)
  • NEVER change the $1000 prompt scoring criteria referenced in research
  • NEVER add runtime dependencies to package.json (this is a pure markdown skill)
  • NEVER commit .private/ contents
  • NEVER use ${{ }} directly inside GitHub Actions run: blocks -- MUST use env vars to prevent script injection

Landmines

  • skills/nv-context/SKILL.md (462 lines): 38 lines from the 500-line hard cap. Every line added MUST justify removing another. The skill loads into agent context on every invocation -- bloat here costs tokens across every user's session.
  • skills/nv-context/*.template files: These are OBSOLETE. SKILL.md v3 generates all content inline per the "Commands Beat Prose" law. Templates remain as reference examples only -- NEVER reference them from SKILL.md as @imports.
  • hooks/learn-from-reviews.yml (line 21): Contains a script injection vulnerability -- ${{ github.event.review.body }} is interpolated directly in a run: block. MUST use env: indirection instead. See SKILL.md Phase 7 for the correct pattern.
  • hooks/settings.json.template: Placeholder commands [FORMAT_COMMAND], [LINT_COMMAND], [TEST_COMMAND] -- these are meant to be replaced per-project by the skill, not used as-is.
  • agents/ and commands/ directories: Empty placeholders. Do not add files here without a design decision on the distribution model.
  • docs/QUICKSTART.md (line 12,19): Install URLs reference nv-skills repo name but the actual repo is nv-context. MUST stay in sync with package.json repository.url.

Read the full file on GitHub · 79 lines

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 · 79 lines · 905 tokens per session scan C 8649114bef0a

Subscribe to this mod's changes

nv-context AGENTS.md is an instructions file published in the GitHub repository johnnichev/nv-context (7 stars, last pushed 6mo ago), licensed MIT. It adds 905 tokens to every session, about $0.0036 per session on Opus 5.5. A static security scan graded it C with 1 finding (hidden instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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