Extension

An Extension is a code package that runs in its own background process. In 0.1.41 it registers Connectors: the parts that send and receive messages between an outside channel and Cowork's Gateway. With the browser permission it can also read and act on the pages of the websites it names.

How it goes live

1. Put the package in <Cowork home>/extensions/packages/<name>/, or use Install from folder in Settings › Extensions, which copies a folder there.
2. Settings › Extensions shows it as waiting for approval. Nothing in it runs yet.
3. You approve it and switch it on. Cowork starts its process and calls its activate function.
4. If any file in the folder changes, it waits for approval again.

The package

File or folder	What it holds
package.json	name, which must equal the folder name (lowercase letters, digits and hyphens); version; description; pi.extensions, which lists exactly one entry file; and the Cowork section, which declares connectors, capabilities, origins and platforms
The entry file, for example index.mjs	Exports activate(api), which calls api.registerConnector(...) for each declared Connector
<Cowork home>/extensions/logs/<name>.log	What the Extension writes to its log; Cowork writes the file
<Cowork home>/extensions/data/<name>/	The Extension's own folder for its data; its process runs in this folder

What it can declare

Item	Meaning
connectors	The IDs of the Connectors it registers. Registering an ID that is not listed is refused
capabilities	browser to act on web pages; audio (needs browser) to capture a page's sound; platform-gate-v1 to use platforms
origins	With browser: the exact websites it may use, from 1 to 20, such as https://example.com
platforms	The computers it supports: darwin-arm64, darwin-x64, win32-x64

A Connector

A Connector has an id and three functions. start(ctx) starts it: open connections and timers here, not in activate; it has 5 seconds. stop() must be safe to call more than once; it has 5 seconds. send(reply) delivers one reply to the channel; it has 30 seconds. Through ctx, the Connector hands incoming messages to Cowork (ctx.emit), writes to its log (ctx.log), and, with the browser permission, uses ctx.browser.

Limits

• Only you can approve an Extension. The AI cannot.
• The approval covers the exact files you approved. Changing one byte means approving again.
• A package can have at most 200 files and 5 MB. Packages from npm and dependencies are not installed.
• If the process crashes, Cowork restarts it after a short wait.
• In 0.1.41 an Extension cannot add tools or commands for the AI. To give the AI a new method, write a Skill.

Related

• Extensions Install, approve and switch on an Extension
• Gateway: Outside Messages Where Connector messages go
• Injection Scripts an Extension runs inside web pages