Team brainstorm

A shared, session-only brainstorm board for a person and Copilot.

Install

copilot plugin marketplace add OWNER/REPO
copilot plugin install team-brainstorm@MARKETPLACE

Replace OWNER/REPO with the GitHub repository that hosts this marketplace and MARKETPLACE with the name in its marketplace.json. See Install plugins for VS Code.

How it works

The skill opens marketplace-starter-brainstorm. The human edits notes in the page; the agent uses get_board, save_note, and remove_note. Server-sent events keep human and agent changes visible without polling.

There are three columns: Ideas, Questions, Next. Edit a note to change its column. Incoming updates preserve keyboard focus on the same note control, including when a note moves columns. If that note is deleted, focus returns to the input. Each session owns one in-memory board, shared by its panels. Reopening a panel preserves notes. Ending or reloading the extension discards them. No export, disk storage, external services, or credentials.

Node.js 22.12+ and a Copilot host with SDK canvas presentation are required. The runtime resolves @github/copilot-sdk/extension; do not install it into the plugin. Hosts without canvas presentation can still use the skill in chat. The loopback server binds only to 127.0.0.1, rejects foreign Host/Origin headers, serves the board only under a random path for each panel, and closes when the runtime closes its instance. These checks stop web pages and casual local requests, not software that runs as your account, so don't put secrets or sensitive data on the board. Copilot and its model also read every note.

Structure

plugin.json
skills/team-brainstorm/SKILL.md
com.github.copilot/extensions/brainstorm/
  extension.mjs     # SDK registration, actions, lifecycle
  board.mjs         # Session-local note model and validation
  server.mjs        # Loopback HTTP and event stream
  index.html        # Plain HTML, CSS, and browser JavaScript

Customize

Change the skill's workflow to match your team's planning habits. Change column names in the board model, page, and skill together. Choose a distinctive canvas ID when copying the plugin so independently installed examples do not collide. Keep server and action input validation in the shared model.

Host checks

Before a release, try these by hand in each host you support. Automated tests and evals don't prove that a host loads or shows everything.

• Open the canvas, and add, edit, move, and delete notes from the page and from chat.
• Reopen the same panel and confirm the notes remain; a new session starts empty.
• Keep keyboard focus on a note control while Copilot edits or moves that note, and confirm focus stays there, or returns to the input if the note is deleted.
• In a host without canvases, confirm the skill keeps the brainstorm in chat.
• If you rename the canvas, update both its ID in the extension and the skill's reference to it.