CodexHost is a desktop application that lets users run coding-agent harnesses such as Pi and Claude Code inside Codex Desktop. It is for people who want to choose among multiple agents and have them delegate tasks to one another while staying in one workspace.
Borrowing it
Nothing to install: this file belongs to BytePioneer-AI/codex-host. 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/BytePioneer-AI/codex-host/main/AGENTS.mdgit clone --depth 1 https://github.com/BytePioneer-AI/codex-hostWrote 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/bytepioneer-ai/codex-host/agents-md)<a href="https://agentmods.dev/instructions/bytepioneer-ai/codex-host/agents-md"><img src="https://agentmods.dev/badge/instructions/bytepioneer-ai/codex-host/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/bytepioneer-ai/codex-host/agents-md"><img src="https://agentmods.dev/badge/instructions/bytepioneer-ai/codex-host/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 | $0.01558 | $0.01558 |
| Opus 5.5 | $0.00623 | $0.00623 |
| Sonnet 5.5 | $0.00312 | $0.00312 |
| Haiku 4.5 | $0.00156 | $0.00156 |
Grade A, and why
codex-host 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 13d 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.
The source is not reproduced here
Licensed LGPL-3.0
The repository is licensed LGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
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.
- 13d ago Changed · -5 lines · -96 tokens per session 00bbab0afcef
- 19d ago Changed · +1 lines · +34 tokens per session 018476dfae2e
- 28d ago Changed · +2 lines · +53 tokens per session 631b19c71d29
- 1mo ago Changed · +19 lines · +399 tokens per session fd5e96c653dd
- 1mo ago Changed · +2 lines · +88 tokens per session c89273083191
- 1mo ago Changed · +6 lines · +251 tokens per session 47ac5f94a6d6
- 1mo ago First seen · 73 lines · 829 tokens per session scan A eb96a395e41f
codex-host AGENTS.md is an instructions file published in the GitHub repository BytePioneer-AI/codex-host (2,982 stars, last pushed yesterday), licensed LGPL-3.0. It adds 1,558 tokens to every session, about $0.0062 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.