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/skills/codexhost-add-harness/SKILL.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/skills/bytepioneer-ai/codex-host/codexhost-add-harness)<a href="https://agentmods.dev/skills/bytepioneer-ai/codex-host/codexhost-add-harness"><img src="https://agentmods.dev/badge/skills/bytepioneer-ai/codex-host/codexhost-add-harness/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/skills/bytepioneer-ai/codex-host/codexhost-add-harness"><img src="https://agentmods.dev/badge/skills/bytepioneer-ai/codex-host/codexhost-add-harness.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00102 | $0.02152 |
| Opus 5.5 | $0.00041 | $0.00861 |
| Sonnet 5.5 | $0.00020 | $0.00430 |
| Haiku 4.5 | $0.00010 | $0.00215 |
Grade A, and why
codexhost-add-harness 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 4d 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 ships with it
13 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- references/capabilities-template.md 3.7 KB
- references/capability-inventory.md 11 KB
- references/implementations.md 7.5 KB
- references/interface-index.md 7.2 KB
- references/packaging-and-validation.md 9.6 KB
- references/spec-connections.md 6.5 KB
- references/spec-delegation.md 6.1 KB
- references/spec-desktop.md 4.5 KB
- references/spec-history.md 8.8 KB
- references/spec-output-interactions.md 8.8 KB
- references/spec-prewarm-idle.md 2.0 KB
- references/spec-session-core.md 9.2 KB
- references/spec-usage-accounts.md 5.7 KB
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.
- 4d ago Changed · -7 lines · +36 tokens per session d2312c7c7afb
- 1mo ago Changed b3ac2e48fea7
- 1mo ago Changed a2a40197ecb6
- 1mo ago Changed · +54 lines · -17 tokens per session d8bfc580ace1
- 1mo ago First seen · 65 lines · 83 tokens per session scan A 3f8ee2945c6f
codexhost-add-harness is a skill published in the GitHub repository BytePioneer-AI/codex-host (2,982 stars, last pushed yesterday), licensed LGPL-3.0. It adds 102 tokens to every session and 2,152 once invoked, about $0.0004 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.
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Use when recent Linux desktop activity memory would help answer a question or when the user asks to inspect or control Chronicle or Skysight.
dg-piagent
A development guide for the pi-agent software kit, used to build and customize coding agents. It covers agents, tools, prompts, sessions, models, authentication, and connected files.
agent-workspace-linux
Use when a task needs an isolated hidden Linux desktop or workspace-owned browser: GUI app QA, web/browser/shopping automation, sandboxed app observation, or stale workspace cleanup. Routes agent-workspace-linux MCP tools on demand. Does NOT apply to host desktop/Chrome control, generic MCP setup, or pure code/file…
prose-review
Review prose written for others (e.g., user-facing documentation, prompts for other LLMs, reports, plans, inline comments, docstrings) for local jargon leakage, orphaned references, missing grounding, and audience or genre mismatch. Always run on prose you produce or materially edit, except for routine conversational…