Add Brainmax Canvas Extension

[juliamuiruri4]

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• I have read and followed the Guidance for submissions involving paid services.
• My contribution adds a new instruction, prompt, agent, skill, workflow, or canvas extension file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested my instructions, prompt, agent, skill, workflow, or canvas extension with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.
• I am targeting the main branch for this pull request.

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Description

BrainMax Canvas is the interactive dashboard for codebase-grounded concept-mastery quizzes. It presents detected knowledge domains, accepts freeform answers, shows rubric scores, and compiles completed domains into a competency report.

The Canvas is an optional visual layer. Question generation and scoring stay with the BrainMaxxing Agent Skills, and the skills continue to work in clients without Canvas support.

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Type of Contribution

• New instruction file.
• New prompt file.
• New agent file.
• New plugin.
• New skill file.
• New agentic workflow.
• New canvas extension.
• Update to existing instruction, prompt, agent, plugin, skill, workflow, or canvas extension.
• Other (please specify):

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Additional Notes

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By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.

[Copilot]

Pull request overview

Adds BrainMax Canvas, an interactive quiz and competency-report extension for the GitHub Copilot marketplace.

Changes:

• Adds the Canvas server, state machine, and SDK actions.
• Adds an accessible, responsive browser interface.
• Registers the extension in the marketplace.

Show a summary per file

File	Description
extensions/brainmax-canvas/README.md	Documents installation and usage.
extensions/brainmax-canvas/public/styles.css	Defines themes and responsive styling.
extensions/brainmax-canvas/public/index.html	Provides the Canvas UI structure.
extensions/brainmax-canvas/public/app.js	Renders state and handles interactions.
extensions/brainmax-canvas/package.json	Defines package metadata and scripts.
extensions/brainmax-canvas/lib/state.mjs	Manages quiz instance state.
extensions/brainmax-canvas/lib/http-server.test.mjs	Tests request-body handling.
extensions/brainmax-canvas/lib/http-server.mjs	Serves UI, SSE, and event endpoints.
extensions/brainmax-canvas/extension.mjs	Implements Canvas actions and lifecycle.
extensions/brainmax-canvas/.github/plugin/plugin.json	Defines extension marketplace metadata.
.github/plugin/marketplace.json	Registers BrainMax Canvas.

Review details

• Files reviewed: 11/12 changed files
• Comments generated: 4
• Review effort level: Medium

[Copilot]

Review details

• Files reviewed: 11/12 changed files
• Comments generated: 5
• Review effort level: Medium

[Copilot]

Review details

• Files reviewed: 11/12 changed files
• Comments generated: 4
• Review effort level: Medium

[Copilot]

Review details

• Files reviewed: 11/12 changed files
• Comments generated: 3
• Review effort level: Medium

[Copilot]

Review details

• Files reviewed: 11/12 changed files
• Comments generated: 3
• Review effort level: Medium

[Copilot]

Review details

• Files reviewed: 11/12 changed files
• Comments generated: 0 new
• Review effort level: Medium

[Copilot]

Review details

Comments suppressed due to low confidence (3)

extensions/brainmax-canvas/extension.mjs:112

• A successful session.send does not guarantee that the agent will invoke record_score. If that follow-up action is omitted, answerStatus never leaves submitting, so the textarea remains disabled and the answer cannot be retried. Detect completion/timeout of the agent turn and restore an actionable error state when no score arrives.

            state.answerStatus = "submitting";

extensions/brainmax-canvas/extension.mjs:160

• This request has the same permanent-pending path: if the agent responds without show_report, the button remains disabled forever because only show_report or a rejected session.send resets the status. Add a session-idle/timeout check that sets reportRequestStatus to error when no report action arrives.

            state.reportRequestStatus = "submitting";

extensions/brainmax-canvas/public/app.js:456

• Web storage access can throw a SecurityError when storage is disabled or restricted. Because this read runs before the EventSource is created, that exception prevents the entire Canvas from connecting; guard both the read and write so theme persistence remains optional.

const storedTheme = localStorage.getItem(THEME_STORAGE_KEY);

• Files reviewed: 11/12 changed files
• Comments generated: 2
• Review effort level: Medium

[Copilot]

Review details

• Files reviewed: 11/12 changed files
• Comments generated: 4
• Review effort level: Medium

[Copilot]

Review details

• Files reviewed: 11/12 changed files
• Comments generated: 0 new
• Review effort level: Medium

[Copilot]

Review details

• Files reviewed: 11/12 changed files
• Comments generated: 0 new
• Review effort level: Medium

[aaronpowell]

Is the BrainMax skill needed to be installed to use this canvas? If so, would it make sense to combine this with the BrainMax repo and have the plugin ship this canvas as part of it using the "external plugins" model?

[Copilot]

Review details

Comments suppressed due to low confidence (1)

extensions/brainmax-canvas/extension.mjs:265

• This action bypasses the state guard used by choose-another-domain (lines 150–152). If the agent invokes show_domains during an active quiz, it silently clears the current question and all quiz progress. Reject the transition unless the current view is summary or report before resetting state.

                        state.view = "domains";
                        state.question = null;
                        state.lastScore = null;
                        state.quiz = null;

• Files reviewed: 11/12 changed files
• Comments generated: 0 new
• Review effort level: Medium

[juliamuiruri4]

Is the BrainMax skill needed to be installed to use this canvas? If so, would it make sense to combine this with the BrainMax repo and have the plugin ship this canvas as part of it using the "external plugins" model?

@aaronpowell Yes, the canvas is dependent on the skills and I agree with your suggested approach to package as an external plugin. Submission created #2468

[aaronpowell]

Closing in favour of #2468