Borrowing it
Nothing to install: this file belongs to arcjet/arcjet-js. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/arcjet/arcjet-js/main/AGENTS.mdgit clone --depth 1 https://github.com/arcjet/arcjet-jsWrote 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.
[](https://agentmods.dev/instructions/arcjet/arcjet-js/agents-md)<a href="https://agentmods.dev/instructions/arcjet/arcjet-js/agents-md"><img src="https://agentmods.dev/badge/instructions/arcjet/arcjet-js/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.
<a href="https://agentmods.dev/instructions/arcjet/arcjet-js/agents-md"><img src="https://agentmods.dev/badge/instructions/arcjet/arcjet-js/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00752 | $0.00752 |
| Opus 5.5 | $0.00301 | $0.00301 |
| Sonnet 5.5 | $0.00150 | $0.00150 |
| Haiku 4.5 | $0.00075 | $0.00075 |
Grade A, and why
arcjet-js 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 6d 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.
How it starts
The opening of the file, as written. The whole thing — 57 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Agent guidance
Examples live in arcjet/examples
Do not add application examples under examples/ in this repository.
Examples were removed from this SDK in
#6217. New and remaining
examples belong in arcjet/examples.
The current migration PR is
arcjet/examples#193 — add
Guard / adapter demos there (or a follow-up on that repo), not here.
That includes:
- Framework apps (
nextjs-*,express-*, …) - Guard integration demos (
nextjs-ai-agent,eve-agent,mastra-agent)
Follow arcjet/examples CONTRIBUTING.md and its canonical example pattern
(package.json metadata, templated README, Dockerfile, compose.yaml,
devcontainer, LICENSE). Pin Arcjet packages to published versions. Standalone
AI examples that need a model key stay out of the default compose/CI matrix.
Do not restore .github/workflows/reusable-examples.yml or re-add an
examples CI job in this repo for new work.
README and skill links should point at
https://github.com/arcjet/examples/tree/main/examples/<name>, not at a
path under this repository.
Agent Skills
JS/TS Agent Skills ship in npm packages via TanStack Intent, not in
arcjet/skills. Keep SKILL.md files beside their source docs
(arcjet-skills/docs/, arcjet-guard/README.md). Validate with
intent validate. Conservative stale checks fail a PR when a declared
source changes and the skill does not. Consumers allowlist packages and
load one skill per task; editor hooks are not a security boundary.
Integration work: review before a PR
For Guard vendor integrations and other integration work, keep going on a branch and push it. Do not open a pull request until David confirms after reviewing the code. The final report must include the exact branch name, commit SHA, and a concise diff summary.
This is NOT the Turborepo you know
Turborepo configuration, task behavior, and CLI commands can vary between installed versions and may differ from your training data. Resolve the turbo package from this file's directory or relevant workspace; in monorepos, it may not be visible from the repository root. For example, run node -p "require.resolve('turbo/package.json')" from a workspace that depends on turbo.
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.
- 6d ago Changed · +11 lines · +300 tokens per session cce96d158c85
- 1mo ago Changed · +9 lines · +101 tokens per session 854263284952
- 1mo ago First seen · 37 lines · 351 tokens per session scan A fd7477c2a0b0
arcjet-js AGENTS.md is an instructions file published in the GitHub repository arcjet/arcjet-js (693 stars, last pushed 2d ago), licensed Apache-2.0. It adds 752 tokens to every session, about $0.0030 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.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).
deno copilot-instructions.md
Copilot instructions for denoland/deno, covering deno development guide for github copilot, network access, high level overview, key directories and key files to understand first.