Borrowing it
Nothing to install: this file belongs to JeongJaeSoon/agent-guard. 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/JeongJaeSoon/agent-guard/main/AGENTS.mdgit clone --depth 1 https://github.com/JeongJaeSoon/agent-guardWrote 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/jeongjaesoon/agent-guard/agents-md)<a href="https://agentmods.dev/instructions/jeongjaesoon/agent-guard/agents-md"><img src="https://agentmods.dev/badge/instructions/jeongjaesoon/agent-guard/agents-md.svg" alt="Measured on agentmods" 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 | $0.00235 | $0.00235 |
| Opus 5 | $0.00118 | $0.00118 |
| Sonnet 5 | $0.00047 | $0.00047 |
| Haiku 4.5 | $0.00023 | $0.00023 |
Grade A, and why
agent-guard 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 2d 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.
What it actually says
Agent Guard contributor rules
Agent Guard is a boundary guard, not an agent orchestrator. Keep these layers separate:
- the portable shell CLI owns policy evaluation, scanning, redaction, exit codes, and dependency diagnostics;
- host adapters (Claude, Codex, Git hooks, and GitHub Actions) translate their native event into the CLI contract and must not duplicate policy logic;
- sub-agent and legacy Task events are inputs to the same boundary checks, not permission to bypass them.
Before adding code, follow this minimum-complexity ladder: reuse an existing path, use POSIX shell or an installed system tool, use a host-native feature, and add a new dependency only when the preceding options cannot provide the required security guarantee. Never simplify away validation, redaction, fail-closed behavior, or cleanup merely to reduce lines.
Every adapter change must preserve safe pass-through behavior for unknown
events, explicit infrastructure-failure policy, and the distinction between a
clean scan and a scan that could not run. Add a fixture for each supported host
and run tests/run.sh before declaring the change complete.
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.
- 2d ago First seen · 23 lines · 235 tokens per session scan A e3aeab715547
agent-guard AGENTS.md is an instructions file published in the GitHub repository JeongJaeSoon/agent-guard (26 stars, last pushed yesterday), licensed MIT. It adds 235 tokens to every session, about $0.0012 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 2026-09-05.
Other instructions, from other repositories
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
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.
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 oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.