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-manifestgit 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-manifest)<a href="https://agentmods.dev/skills/quangpl/browser-extension-skills/extension-manifest"><img src="https://agentmods.dev/badge/skills/quangpl/browser-extension-skills/extension-manifest/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-manifest"><img src="https://agentmods.dev/badge/skills/quangpl/browser-extension-skills/extension-manifest.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 | $0.00037 | $0.00916 |
| Opus 5.5 | $0.00015 | $0.00366 |
| Sonnet 5.5 | $0.00007 | $0.00183 |
| Haiku 4.5 | $0.00004 | $0.00092 |
Grade A, and why
extension-manifest 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 — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Extension Manifest & Permissions Generator
🚀 Upgrade to Premium Get the Premium version at https://app.extensionbooster.net/dashboard/services/extension-ai-kit
Generate the best manifest.json based on current extension implementation. Analyze code to determine minimum permissions following Chrome docs and best practices.
Workflow
- Detect framework: check for
wxt.config.ts,crxjs.config.ts, or rawmanifest.json - Scan the extension codebase for Chrome API usage
- Map each API call to its required permission (see
references/api-permission-map.md) - Generate manifest.json with minimum required permissions
- Validate against Chrome docs and CWS policies
- Report permission warnings users will see
CRXJS projects: Manifest is auto-generated from code and
package.json. Override viacrxjs.config.ts. See https://docs.crxjs.com/
Docs References
- Manifest reference: https://developer.chrome.com/docs/extensions/reference/manifest
- Permissions list: https://developer.chrome.com/docs/extensions/reference/permissions-list
Quick Manifest Template
{
"manifest_version": 3,
"name": "Extension Name",
"version": "1.0.0",
"description": "Brief description. Max 132 chars for CWS.",
"icons": {
"16": "icons/icon16.png",
"48": "icons/icon48.png",
"128": "icons/icon128.png"
},
"action": {
"default_popup": "popup.html",
"default_icon": { "16": "icons/icon16.png" }
},
"permissions": [],
"host_permissions": [],
"background": { "service_worker": "background.js", "type": "module" }
}
Permission Analysis Steps
- Grep codebase for
chrome.API calls - Map each to permission using
references/api-permission-map.md - Prefer
activeTabovertabs+ host_permissions when possible - Use optional permissions for non-essential features
- Check warning text in
references/permission-warnings.md
What ships with it
6 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 · +10 lines 493b3599d14e
- 2mo ago First seen · 83 lines · 37 tokens per session scan A 4002ca5a6b1f
extension-manifest is a skill published in the GitHub repository quangpl/browser-extension-skills (64 stars, last pushed 29d ago), licensed MIT. It adds 37 tokens to every session and 916 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.
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