Browser Extension Connector — Development skill for Claude Code

browser-extension-connector

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An [Agent Skill](https://agentskills.io) that teaches an agent to build a **Chrome MV3** connector for a web service with no usable public API: an extension that observes the service's JSON traffic in the page's own context, replays the page's own auth headers for pulls and writes, buffers what it learns when the network or the host is away, and exchanges all of it with a host app through one polled request. The host app it syncs with is a **Next.js App Router** app in our own use, but its side is a documented contract, so any server that answers two endpoints will do.

**A site with no API still has a signed-in user and a browser that sees every response the site serves.** The plumbing that turns that into a connector is a week's work; the runtime it has to live in is the rest. Chrome evicts an idle service worker after about 30 seconds, `chrome.alarms` will not fire more often than once a minute, a MAIN-world content script with one top-level `export` ships dead and silent, a content script detached by an extension reload throws on every `chrome.*` call forever, and the credential that makes the whole thing possible must never leave the tab it was captured in. This skill is that runtime, with the service itself behind a seam.

This skill was written by the engineer who has shipped this module. The earlier implementation it was audited against wa