yolobox: Instructions file for Codex

AGENTS.md

yolobox AGENTS.md is an instructions file for Codex, OpenCode from finbarr/yolobox. It costs 4,026 tokens per session, scanned C, original, MIT.

A repository-specific instruction file that records how coding agents should make, test, document, and commit changes.

In plain words
What is it for?
Use it to define build, test, lint, verification, release, and user-facing documentation expectations for a code repository.
Why use it?
It gives an agent the project’s working rules and prevents important checks or related documentation updates from being skipped.

Instructions file for CodexOpenCode

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

This is finbarr/yolobox's own configuration. It tells Codex and OpenCode how to work on yolobox 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 yolobox configures →

Not installable: its command points at a path on the author’s own machine, so it runs nowhere else. The line is /home/yolo/.npm-global.

Reuse

Borrowing it

Nothing to install: this file belongs to finbarr/yolobox. 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/finbarr/yolobox/master/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/finbarr/yolobox

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 yolobox AGENTS.md

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

Your own site · 80×15
<a href="https://agentmods.dev/instructions/finbarr/yolobox/agents-md"><img src="https://agentmods.dev/badge/instructions/finbarr/yolobox/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 4,026 This file is loaded in full into every session.
When invoked 4,026 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 $0.04026 $0.04026
Opus 5.5 $0.01610 $0.01610
Sonnet 5.5 $0.00805 $0.00805
Haiku 4.5 $0.00403 $0.00403

Measured yesterday against content hash f7e42a8c4692, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade C, and why

yolobox 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 yesterday.

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.

Recursive force deletehighDestructive command

rm -rf with a variable or a broad path is one typo away from removing the wrong tree.

- Host Codex config import must preserve a valid existing container `/home/yolo/.codex/auth.json` when the host config has no usable auth file. Do not `rm -rf /home/yolo/.codex` before importing host Codex config.
AGENTS.md · 149 lines

How it starts

The opening of the file, as written. The whole thing — 149 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

This file is the working agreement for changes in this repository.

Workflow

Default workflow for this repo:

  1. Make the requested code or docs change directly.
  2. Verify it thoroughly.
  3. Commit the change before finishing.

Whenever behavior, UX, defaults, flags, docs, or built-in agent guidance change, audit the matching user-facing surfaces in this repo and update them too:

Do not stop at unit tests when behavior can be exercised for real. If a change affects runtime behavior, flags, mounts, image builds, config loading, or release automation, run the actual path and verify the output.

If full end-to-end verification is blocked by the environment, state exactly what was run, what was not run, and why.

Any hard-earned lesson that changes how future work should be done belongs in AGENTS.md.

Build Commands

make build          # Build the yolobox binary
make test           # Run unit tests
make lint           # Run go vet (and golangci-lint if installed)
make image          # Build the Docker base image
make smoke-test     # Run smoke tests on container tools
make smoke-acp      # Check both ACP adapters' versions and protocol startup
make install        # Build and install to ~/.local/bin
make clean          # Remove built binary

Verification Standard

For non-trivial code changes, start here:

make clean && make build && make test
make lint
./yolobox version
./yolobox help
./yolobox config

Before any release or tag push, update CHANGELOG.md with the release's user-facing changes. Release tags must be created only from a clean, up-to-date master branch; do not tag feature branches, and push only master plus the specific release tag. make lint is also mandatory and must include the same golangci-lint coverage that CI runs. If local make lint reports golangci-lint not installed, skipping, install/run golangci-lint locally or run the CI linter equivalent before shipping.

Read the full file on GitHub · 149 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. yesterday Changed · +1 lines · +42 tokens per session f7e42a8c4692
  2. 3d ago Changed · +1 lines · +222 tokens per session cd73fd06cf1b
  3. 14d ago Changed · +1 lines · +59 tokens per session 80f201d7527a
  4. 15d ago Changed · +2 lines · +215 tokens per session bad4c33097c3
  5. 16d ago Changed · +3 lines · +134 tokens per session c7960abf41bf
  6. 1mo ago First seen · 141 lines · 3,354 tokens per session scan C e9228c6b4570

Subscribe to this mod's changes

yolobox AGENTS.md is an instructions file published in the GitHub repository finbarr/yolobox (653 stars, last pushed 2d ago), licensed MIT. It adds 4,026 tokens to every session, about $0.0161 per session on Opus 5.5. A static security scan graded it C with 1 finding (recursive force delete). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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