BrowserOS is an open-source browser system that provides a separate browser for AI agents alongside a browser for personal use. Agents use it to perform tasks in logged-in websites while people monitor or replay their sessions.
Borrowing it
Nothing to install: this file belongs to browseros-ai/BrowserOS. 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/browseros-ai/BrowserOS/main/.claude/skills/writing-plans/SKILL.mdgit clone --depth 1 https://github.com/browseros-ai/BrowserOSWrote 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/browseros-ai/browseros/writing-plans)<a href="https://agentmods.dev/skills/browseros-ai/browseros/writing-plans"><img src="https://agentmods.dev/badge/skills/browseros-ai/browseros/writing-plans/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/browseros-ai/browseros/writing-plans"><img src="https://agentmods.dev/badge/skills/browseros-ai/browseros/writing-plans.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 | $0.00022 | $0.01315 |
| Opus 5.5 | $0.00009 | $0.00526 |
| Sonnet 5.5 | $0.00004 | $0.00263 |
| Haiku 4.5 | $0.00002 | $0.00131 |
Grade A, and why
sup-writing-plans 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.
The source is not reproduced here
Licensed AGPL-3.0
The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
What ships with it
1 file 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.
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 · 152 lines · 22 tokens per session scan A 164fc6ba3f69
sup-writing-plans is a skill published in the GitHub repository browseros-ai/BrowserOS (14,261 stars, last pushed yesterday), licensed AGPL-3.0. It adds 22 tokens to every session and 1,315 once invoked, about $0.0001 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.
sup-writing-plans compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| sup-writing-plansbrowseros-ai/BrowserOS | Skill | 14k | yesterday | AGPL-3.0 | A | 22 | Claude Code |
| electron-expertpersonamanagmentlayer/pcl | Skill | 44 | 11d ago | Apache-2.0 | A | 59 | Claude Code |
| agent-computer-usekortix-ai/agent-computer-use | Skill | 68 | 1mo ago | MIT | B | 216 | Claude Code, Codex |
| endpoint-triageellmos-ai/skills | Skill | 9 | 4d ago | MIT | A | 112 | Claude Code, Codex |
| os-hardening-baselineellmos-ai/skills | Skill | 9 | 4d ago | MIT | A | 100 | Claude Code, Codex |
| browser-extensionthewolffish/wolffish-app | Skill | 5 | 1mo ago | MIT | A | 74 | Claude Code, Codex |
| browserthewolffish/wolffish-app | Skill | 5 | 1mo ago | MIT | A | 56 | Claude Code, Codex |