agents-best-practices: Instructions file for Codex

AGENTS.md

agents-best-practices AGENTS.md is an instructions file for Codex, OpenCode from laguagu/agents-best-practices. It costs 250 tokens per session, scanned A, original, Apache-2.0.

Project instructions for a repository of best practices for coding-agent skills. A skill is a reusable set of instructions for an agent, and the file covers its structure, conventions, common mistakes, and editing checks.

In plain words
What is it for?
Use them when creating or editing skills, checking descriptions and references, pinning script dependencies, or running the required audits.
Why use it?
They help keep skills consistent, self-contained, testable, and easy for agents to select correctly.

Instructions file for CodexOpenCode

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

This is laguagu/agents-best-practices's own configuration. It tells Codex and OpenCode how to work on agents-best-practices 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 agents-best-practices configures →

Reuse

Borrowing it

Nothing to install: this file belongs to laguagu/agents-best-practices. 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/laguagu/agents-best-practices/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/laguagu/agents-best-practices

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 agents-best-practices AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/laguagu/agents-best-practices/agents-md.svg)](https://agentmods.dev/instructions/laguagu/agents-best-practices/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/laguagu/agents-best-practices/agents-md"><img src="https://agentmods.dev/badge/instructions/laguagu/agents-best-practices/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 250 This file is loaded in full into every session.
When invoked 250 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 $0.00250 $0.00250
Opus 5 $0.00125 $0.00125
Sonnet 5 $0.00050 $0.00050
Haiku 4.5 $0.00025 $0.00025

Measured 7d ago against content hash 4a598d522554, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

agents-best-practices 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 7d 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.

AGENTS.md · 29 lines

What it actually says

Agent Instructions

This repository contains best practices for the .agents/skills/ ecosystem.

Structure

  • .agents/skills/ — Working skills (improving-skills, skill-creator, skill-finder)

Conventions

  • Use forward slashes in all paths (scripts/helper.py not scripts\helper.py)
  • Keep SKILL.md under 500 lines; use references/ only when it reduces bloat
  • Pin dependency versions in scripts (npx [email protected], uv run [email protected])
  • Write descriptions in third person with explicit trigger contexts
  • Every skill must pass: name matches directory, description under 1024 chars

Gotchas

  • This repo is a governance/best-practices resource — it practices what it preaches
  • Skills must be self-contained — no references to files outside the skill directory

When Editing Skills

  1. Read the current SKILL.md before making changes
  2. Run the improving-skills audit after changes
  3. Verify description stays under 1024 characters
  4. Test trigger accuracy with at least 3 manual prompts
  5. Ensure all referenced files exist
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. 7d ago First seen · 29 lines · 250 tokens per session scan A 4a598d522554

Subscribe to this mod's changes

agents-best-practices AGENTS.md is an instructions file published in the GitHub repository laguagu/agents-best-practices (2 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 250 tokens to every session, about $0.0013 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 2026-08-31.

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