Browser Extension Builder Agent Skill

Expert in building browser extensions that solve real problems - Chrome, Firefox, and cross-browser extensions. Covers extension architecture, manifest v3, content scripts, popup UIs, monetization strategies, and Chrome Web Store publishing. Use when: browser extension, chrome extension, firefox addon, extension, manifest v3.

2k tokens

context cost

the whole folder, loaded on every use

files

instructions only

copies elsewhere

how many repositories repackaged it

505

stars on the repo

on the repository, not the skill itself

Install

one command, takes just this skill from the repository

npx skills add https://github.com/Dokhacgiakhoa/Agent-Skills-4-Vibe-Coding-CLI --skill browser-extension-builder

What comes with it

4 947 bytes besides the instruction

sub-skills/asyncawait-pattern.md

sub-skills/basic-content-script.md

sub-skills/breaking-on-updates.md

sub-skills/chrome-storage-api.md

sub-skills/communication-pattern.md

sub-skills/content-scripts.md

sub-skills/extension-architecture.md

sub-skills/heavy-background-processing.md

sub-skills/injecting-ui.md

sub-skills/manifest-v3-template.md

sub-skills/permissions-for-content-scripts.md

sub-skills/project-structure.md

sub-skills/requesting-all-permissions.md

sub-skills/storage-and-state.md

sub-skills/storage-limits.md

The instruction itself

19 sections, as written by the author

Browser Extension Builder

Role: Browser Extension Architect

You extend the browser to give users superpowers. You understand the

unique constraints of extension development - permissions, security,

store policies. You build extensions that people install and actually

use daily. You know the difference between a toy and a tool.

Capabilities

Extension architecture
Manifest v3 (MV3)
Content scripts
Background workers
Popup interfaces
Extension monetization
Chrome Web Store publishing
Cross-browser support

Patterns

🧠 Knowledge Modules (Fractal Skills)

1. Extension Architecture

2. Project Structure

3. Manifest V3 Template

4. Communication Pattern

5. Content Scripts

6. Basic Content Script

7. Injecting UI

8. Permissions for Content Scripts

9. Storage and State

10. Chrome Storage API

11. Storage Limits

12. Async/Await Pattern

13. ❌ Requesting All Permissions

14. ❌ Heavy Background Processing

15. ❌ Breaking on Updates

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How to use it

Copy the folder

Take dokhacgiakhoa/browser-extension-builder from the repository into ~/.claude/skills for personal use, or into .claude/skills inside a project.

Check the name does not clash

The agent identifies a skill by the name field in its header. Two skills with the same name cannot sit side by side — one of them will be ignored.