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 quangpl/browser-extension-skills --skill extension-creategit clone --depth 1 https://github.com/quangpl/browser-extension-skillsWrote 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/quangpl/browser-extension-skills/extension-create)<a href="https://agentmods.dev/skills/quangpl/browser-extension-skills/extension-create"><img src="https://agentmods.dev/badge/skills/quangpl/browser-extension-skills/extension-create/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/quangpl/browser-extension-skills/extension-create"><img src="https://agentmods.dev/badge/skills/quangpl/browser-extension-skills/extension-create.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 | $0.00039 | $0.01222 |
| Opus 5.5 | $0.00016 | $0.00489 |
| Sonnet 5.5 | $0.00008 | $0.00244 |
| Haiku 4.5 | $0.00004 | $0.00122 |
Grade A, and why
extension-create 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 146 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Extension Create (WXT & CRXJS)
🚀 Upgrade to Premium Get the Premium version at https://app.extensionbooster.net/dashboard/services/extension-ai-kit
Auto-scaffold a Chrome extension project. Do NOT just explain — execute the workflow.
Workflow (Execute This)
Step 1: Gather requirements from user
Ask the user to confirm:
- Extension name (kebab-case, e.g.
my-tab-manager) - Short description (1 sentence)
- UI framework: React / Vue / Svelte / Vanilla (default: React)
- Features needed (pick from list below):
- Popup UI
- Content script (modify pages)
- Background service worker
- Side panel
- Options page
- Context menu
- Tab management / Storage / Active tab only
Step 2: Pick scaffolder based on framework choice
| Framework | Recommended Scaffolder | Why |
|---|---|---|
| React | CRXJS or WXT | CRXJS has CSUI, quickstarts |
| Vue | WXT | First-class Vue support |
| Svelte | WXT | First-class Svelte support |
| Vanilla TS | WXT | Lightest setup |
Step 3: Scaffold
WXT — multi-framework, file-based entrypoints:
npx wxt@latest init <name> --template <react|vue|svelte|vanilla>
cd <name> && pnpm install
CRXJS — React-first, auto-manifest, rich quickstarts:
# Basic React
npm create crxjs
# With Tailwind CSS
npm create crxjs
# With specific template (see https://crxjs.dev/)
npm create crxjs
Quickstarts: https://crxjs.dev/ Full docs: https://crxjs.dev/
Step 3: Configure based on features
WXT: Edit wxt.config.ts with permissions and manifest fields.
CRXJS: Edit vite.config.ts or manifest.json. CRXJS handles manifest using vite config.
Step 4: Create entrypoints
Create files in entrypoints/ based on chosen features (see below).
What ships with it
4 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.
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.
- 1mo ago Changed · +7 lines 579b05e875ae
- 1mo ago First seen · 139 lines · 39 tokens per session scan A b6d3161a1210
extension-create is a skill published in the GitHub repository quangpl/browser-extension-skills (63 stars, last pushed 24d ago), licensed MIT. It adds 39 tokens to every session and 1,222 once invoked, about $0.0002 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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