Borrowing it
Nothing to install: this file belongs to 0xferrous/agent-box. 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/0xferrous/agent-box/main/AGENTS.mdgit clone --depth 1 https://github.com/0xferrous/agent-boxWrote 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/0xferrous/agent-box/agents-md)<a href="https://agentmods.dev/instructions/0xferrous/agent-box/agents-md"><img src="https://agentmods.dev/badge/instructions/0xferrous/agent-box/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/0xferrous/agent-box/agents-md"><img src="https://agentmods.dev/badge/instructions/0xferrous/agent-box/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 | $0.00373 | $0.00373 |
| Opus 5.5 | $0.00149 | $0.00149 |
| Sonnet 5.5 | $0.00075 | $0.00075 |
| Haiku 4.5 | $0.00037 | $0.00037 |
Grade A, and why
agent-box 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 2mo 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
- use
nix develop --commandto run the commands in the flake's devshell - use conventionalcommits.org pattern when writing commit messages
pre commit
- format code with
cargo fmt - check code with
cargo check - check clippy with
cargo clippy - always keep the docs and README files in sync with the code changes (root and crate-level READMEs)
- keep the table of contents in the root
README.mdup to date whenever a change is made
image
The image flake uses a custom docker.nix from the nix input (github:0xferrous/nix/extra-args).
To get the nix store path of the nix flake input:
nix eval --raw --impure --expr '(builtins.getFlake (toString ./image)).inputs.nix'
# Returns: /nix/store/<hash>-source
To read the docker.nix file from that input:
cat $(nix eval --raw --impure --expr '(builtins.getFlake (toString ./image)).inputs.nix')/docker.nix
This is referenced in image/flake.nix as:
pkgs.callPackage "${nix}/docker.nix" { ... }
wrappers
- implement wrapper binaries in Rust (keep wrapper runtime language consistent across
wrappers/)
portal ADR
- Portal architecture decisions are tracked in
adr/. - Current accepted ADRs:
adr/0001-agent-portal.mdadr/0002-transparent-portal-wrappers.md
- For portal work, keep implementation and configuration aligned with these ADRs.
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.
- 2mo ago First seen · 45 lines · 373 tokens per session scan A d65f282c3c18
agent-box AGENTS.md is an instructions file published in the GitHub repository 0xferrous/agent-box (40 stars, last pushed 5mo ago), licensed MIT. It adds 373 tokens to every session, about $0.0015 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.
agent-box AGENTS.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| agent-box AGENTS.md0xferrous/agent-box | Instructions file | 40 | 5mo ago | MIT | A | 373 | Codex, OpenCode |
| vscode buildNext.instructions.mdmicrosoft/vscode | Instructions file | 195k | yesterday | MIT | A | 9,719 | GitHub Copilot |
| next.js AGENTS.mdvercel/next.js | Instructions file | 143k | yesterday | MIT | A | 7,461 | Codex, OpenCode |
| langchain AGENTS.mdlangchain-ai/langchain | Instructions file | 149k | yesterday | MIT | A | 4,680 | Codex, OpenCode |
| vscode oss-third-party-notices.instructions.mdmicrosoft/vscode | Instructions file | 195k | yesterday | MIT | A | 5,516 | GitHub Copilot |
| vscode copilot-instructions.mdmicrosoft/vscode | Instructions file | 195k | yesterday | MIT | A | 3,093 | GitHub Copilot |
| deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness | Instructions file | 274k | 2d ago | MIT | A | 4,313 | Codex, OpenCode |