Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add devinilabs/pro-skill --skill container-linesgit clone --depth 1 https://github.com/devinilabs/pro-skillWrote 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/devinilabs/pro-skill/container-lines)<a href="https://agentmods.dev/skills/devinilabs/pro-skill/container-lines"><img src="https://agentmods.dev/badge/skills/devinilabs/pro-skill/container-lines.svg" alt="Measured on agentmods" 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 | $0.00046 | $0.00892 |
| Opus 5 | $0.00023 | $0.00446 |
| Sonnet 5 | $0.00009 | $0.00178 |
| Haiku 4.5 | $0.00005 | $0.00089 |
Grade A, and why
container-lines 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 3d 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.
This is a copy
100% identical to container-lines — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 120 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Container Lines
Use When
- A page needs subtle vertical guides that reveal the content container width.
- A hero, section, or product page feels too loose and needs structural tension.
- The design calls for mini corner squares, measured edges, or quiet technical framing.
Rules
- Draw lines at the left and right edges of the main content container.
- Keep lines thin:
1pxwith low opacity. - Add mini squares at container corners or section intersections.
- Keep the line system consistent across sections; do not change width per section.
- Place lines behind content but above the page background.
- Disable pointer events so the guides never block UI.
Base Tokens
:root {
--container-max: 1120px;
--container-pad: clamp(20px, 4vw, 48px);
--line-color: rgba(24, 24, 27, 0.14);
--line-strong: rgba(24, 24, 27, 0.28);
--corner-size: 6px;
}
Page Container Lines
Use pseudo-elements on the layout shell.
.container-lines {
position: relative;
isolation: isolate;
}
.container-lines::before,
.container-lines::after {
content: "";
position: absolute;
top: 0;
bottom: 0;
z-index: -1;
width: 1px;
background: var(--line-color);
pointer-events: none;
}
.container-lines::before {
left: max(var(--container-pad), calc((100vw - var(--container-max)) / 2));
}
.container-lines::after {
right: max(var(--container-pad), calc((100vw - var(--container-max)) / 2));
}
Corner Squares
Add four small squares to sections that need a precise measured feel.
.corner-squares {
position: relative;
}
.corner-squares > .corner {
position: absolute;
width: var(--corner-size);
height: var(--corner-size);
background: var(--line-strong);
pointer-events: none;
}
.corner.top-left { top: 0; left: 0; transform: translate(-50%, -50%); }
.corner.top-right { top: 0; right: 0; transform: translate(50%, -50%); }
.corner.bottom-left { bottom: 0; left: 0; transform: translate(-50%, 50%); }
.corner.bottom-right { right: 0; bottom: 0; transform: translate(50%, 50%); }
What ships with it
11 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.
- demo/assets/page-01-65695f80-23f9-46ee-8487-cbb6c93cc48b-3840w.webp 524 KB
- demo/assets/page-02-724142aa-44a6-48d3-9cf3-761e00d05b78-1600w.jpg 966 KB
- demo/assets/page-03-4734259a-bad7-422f-981e-ce01e79184f2-1600w.jpg 44 KB
- demo/assets/page-04-005600e5-f6ab-4e59-bc86-eaeb02797dfa-1600w.jpg 712 KB
- demo/assets/page-05-e534354d-c5f2-4399-a1d9-2f50338e8c47-1600w.jpg 83 KB
- demo/assets/page-06-fb6415fd-bf4d-4ccf-8e9d-7ab445e99207-1600w.jpg 197 KB
- demo/assets/source-preview.jpg 136 KB
- demo/index.html 44 KB
- demo/preview.jpg 96 KB
- demo/PROMPT.md 2.5 KB
- demo/source.json 4.4 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.
- 3d ago First seen · 120 lines · 46 tokens per session scan A b2eb19356c14
container-lines is a skill published in the GitHub repository devinilabs/pro-skill (23 stars, last pushed 24d ago), licensed MIT. It adds 46 tokens to every session and 892 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to container-lines, differing in 0 lines, and is treated as a copy.
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