deploy: current vibn theia state

Made-with: Cursor

packages/ai-copilot/.eslintrc.js

@@ -0,0 +1,10 @@
+/** @type {import('eslint').Linter.Config} */
+module.exports = {
+    extends: [
+        '../../configs/build.eslintrc.json'
+    ],
+    parserOptions: {
+        tsconfigRootDir: __dirname,
+        project: 'tsconfig.json'
+    }
+};

packages/ai-copilot/README.md

@@ -0,0 +1,73 @@
+<div align='center'>
+
+<br />
+
+<img src='https://raw.githubusercontent.com/eclipse-theia/theia/master/logo/theia.svg?sanitize=true' alt='theia-ext-logo' width='100px' />
+
+<h2>ECLIPSE THEIA - GITHUB COPILOT EXTENSION</h2>
+
+<hr />
+
+</div>
+
+## Description
+
+The `@theia/ai-copilot` extension integrates GitHub Copilot language models with Theia AI.
+This allows users to authenticate with their GitHub Copilot subscription and use Copilot models (e.g., GPT-4o, Claude Sonnet) through Theia's AI features.
+
+### Authentication
+
+The extension uses GitHub's OAuth Device Flow for authentication:
+
+1. Click the "Copilot" status bar item or run the **Copilot: Sign In** command
+2. A dialog appears with a device code - click the link to open GitHub's device authorization page
+3. Enter the code and authorize the application
+4. The dialog updates to show "Authenticated" and the status bar reflects the signed-in state
+
+Once authenticated, Copilot models become available in the AI Configuration for use with any Theia AI agent.
+
+> **Note:** This extension requires an active GitHub Copilot subscription.
+
+### Configuration
+
+Available models can be configured via the `ai-features.copilot.models` preference:
+
+```json
+{
+    "ai-features.copilot.models": [
+        "gpt-4o",
+        "claude-sonnet-4"
+    ]
+}
+```
+
+### GitHub Enterprise
+
+For GitHub Enterprise users, configure the enterprise URL via the `ai-features.copilot.enterpriseUrl` preference:
+
+```json
+{
+    "ai-features.copilot.enterpriseUrl": "github.mycompany.com"
+}
+```
+
+### Commands
+
+- **Copilot: Sign In** - Initiates the OAuth device flow authentication
+- **Copilot: Sign Out** - Signs out and clears stored credentials
+
+## Additional Information
+
+- [API documentation for `@theia/ai-copilot`](https://eclipse-theia.github.io/theia/docs/next/modules/_theia_ai-copilot.html)
+- [Theia - GitHub](https://github.com/eclipse-theia/theia)
+- [Theia - Website](https://theia-ide.org/)
+
+## License
+
+- [Eclipse Public License 2.0](http://www.eclipse.org/legal/epl-2.0/)
+- [一 (Secondary) GNU General Public License, version 2 with the GNU Classpath Exception](https://projects.eclipse.org/license/secondary-gpl-2.0-cp)
+
+## Trademark
+
+"Theia" is a trademark of the Eclipse Foundation
+<https://www.eclipse.org/theia>

packages/ai-copilot/package.json

@@ -0,0 +1,51 @@
+{
+  "name": "@theia/ai-copilot",
+  "version": "1.68.0",
+  "description": "Theia - GitHub Copilot Integration",
+  "dependencies": {
+    "@theia/ai-core": "1.68.0",
+    "@theia/ai-openai": "1.68.0",
+    "@theia/core": "1.68.0",
+    "openai": "^6.3.0",
+    "tslib": "^2.6.2"
+  },
+  "publishConfig": {
+    "access": "public"
+  },
+  "theiaExtensions": [
+    {
+      "frontend": "lib/browser/copilot-frontend-module",
+      "backend": "lib/node/copilot-backend-module"
+    }
+  ],
+  "keywords": [
+    "theia-extension"
+  ],
+  "license": "EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/eclipse-theia/theia.git"
+  },
+  "bugs": {
+    "url": "https://github.com/eclipse-theia/theia/issues"
+  },
+  "homepage": "https://github.com/eclipse-theia/theia",
+  "files": [
+    "lib",
+    "src"
+  ],
+  "scripts": {
+    "build": "theiaext build",
+    "clean": "theiaext clean",
+    "compile": "theiaext compile",
+    "lint": "theiaext lint",
+    "test": "theiaext test",
+    "watch": "theiaext watch"
+  },
+  "devDependencies": {
+    "@theia/ext-scripts": "1.68.0"
+  },
+  "nyc": {
+    "extends": "../../configs/nyc.json"
+  }
+}

packages/ai-copilot/src/browser/copilot-auth-dialog.tsx

@@ -0,0 +1,326 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import * as React from '@theia/core/shared/react';
+import { inject, injectable, postConstruct } from '@theia/core/shared/inversify';
+import { DialogProps, DialogError } from '@theia/core/lib/browser/dialogs';
+import { ReactDialog } from '@theia/core/lib/browser/dialogs/react-dialog';
+import { ClipboardService } from '@theia/core/lib/browser/clipboard-service';
+import { WindowService } from '@theia/core/lib/browser/window/window-service';
+import { CommandService, nls } from '@theia/core';
+import { CopilotAuthService, DeviceCodeResponse } from '../common/copilot-auth-service';
+
+const OPEN_AI_CONFIG_VIEW_COMMAND = 'aiConfiguration:open';
+
+type AuthDialogState = 'loading' | 'waiting' | 'polling' | 'success' | 'error';
+
+@injectable()
+export class CopilotAuthDialogProps extends DialogProps {
+    enterpriseUrl?: string;
+}
+
+@injectable()
+export class CopilotAuthDialog extends ReactDialog<boolean> {
+
+    @inject(CopilotAuthService)
+    protected readonly authService: CopilotAuthService;
+
+    @inject(ClipboardService)
+    protected readonly clipboardService: ClipboardService;
+
+    @inject(WindowService)
+    protected readonly windowService: WindowService;
+
+    @inject(CommandService)
+    protected readonly commandService: CommandService;
+
+    protected state: AuthDialogState = 'loading';
+    protected deviceCodeResponse?: DeviceCodeResponse;
+    protected errorMessage?: string;
+    protected copied = false;
+
+    static readonly ID = 'copilot-auth-dialog';
+
+    constructor(
+        @inject(CopilotAuthDialogProps) protected override readonly props: CopilotAuthDialogProps
+    ) {
+        super(props);
+    }
+
+    @postConstruct()
+    protected init(): void {
+        this.titleNode.textContent = nls.localize('theia/ai/copilot/auth/title', 'Sign in to GitHub Copilot');
+        this.appendAcceptButton(nls.localize('theia/ai/copilot/auth/authorize', 'I have authorized'));
+        this.appendCloseButton(nls.localizeByDefault('Cancel'));
+    }
+
+    protected updateButtonStates(): void {
+        const isPolling = this.state === 'polling';
+        const isSuccess = this.state === 'success';
+        if (this.acceptButton) {
+            this.acceptButton.disabled = isPolling || isSuccess;
+            if (isSuccess) {
+                this.acceptButton.style.display = 'none';
+            }
+        }
+        if (this.closeButton) {
+            if (isSuccess) {
+                this.closeButton.textContent = nls.localizeByDefault('Close');
+            }
+        }
+    }
+
+    override async open(): Promise<boolean | undefined> {
+        this.initiateFlow();
+        return super.open();
+    }
+
+    override update(): void {
+        super.update();
+        this.updateButtonStates();
+    }
+
+    protected async initiateFlow(): Promise<void> {
+        try {
+            this.state = 'loading';
+            this.update();
+
+            this.deviceCodeResponse = await this.authService.initiateDeviceFlow(this.props.enterpriseUrl);
+            this.state = 'waiting';
+            this.update();
+        } catch (error) {
+            this.state = 'error';
+            this.errorMessage = error instanceof Error ? error.message : String(error);
+            this.update();
+        }
+    }
+
+    protected override async accept(): Promise<void> {
+        if (this.state !== 'waiting' || !this.deviceCodeResponse) {
+            return;
+        }
+
+        this.state = 'polling';
+        this.update();
+
+        try {
+            const success = await this.authService.pollForToken(
+                this.deviceCodeResponse.device_code,
+                this.deviceCodeResponse.interval,
+                this.props.enterpriseUrl
+            );
+
+            if (success) {
+                this.state = 'success';
+                this.update();
+            } else {
+                this.state = 'error';
+                this.errorMessage = nls.localize('theia/ai/copilot/auth/expired',
+                    'Authorization expired or was denied. Please try again.');
+                this.update();
+            }
+        } catch (error) {
+            this.state = 'error';
+            this.errorMessage = error instanceof Error ? error.message : String(error);
+            this.update();
+        }
+    }
+
+    get value(): boolean {
+        return this.state === 'success';
+    }
+
+    protected override isValid(_value: boolean, _mode: DialogError): DialogError {
+        if (this.state === 'error') {
+            return this.errorMessage ?? 'An error occurred';
+        }
+        return '';
+    }
+
+    protected handleCopyCode = async (): Promise<void> => {
+        if (this.deviceCodeResponse) {
+            await this.clipboardService.writeText(this.deviceCodeResponse.user_code);
+            this.copied = true;
+            this.update();
+            setTimeout(() => {
+                this.copied = false;
+                this.update();
+            }, 2000);
+        }
+    };
+
+    protected handleOpenUrl = (): void => {
+        if (this.deviceCodeResponse) {
+            this.windowService.openNewWindow(this.deviceCodeResponse.verification_uri, { external: true });
+        }
+    };
+
+    protected render(): React.ReactNode {
+        return (
+            <div className="theia-copilot-auth-dialog-content">
+                {this.renderContent()}
+            </div>
+        );
+    }
+
+    protected renderContent(): React.ReactNode {
+        switch (this.state) {
+            case 'loading':
+                return this.renderLoading();
+            case 'waiting':
+                return this.renderWaiting();
+            case 'polling':
+                return this.renderPolling();
+            case 'success':
+                return this.renderSuccess();
+            case 'error':
+                return this.renderError();
+            default:
+                return undefined;
+        }
+    }
+
+    protected renderLoading(): React.ReactNode {
+        return (
+            <div className="theia-copilot-auth-state">
+                <div className="theia-spin">
+                    <span className="codicon codicon-loading"></span>
+                </div>
+                <p>{nls.localize('theia/ai/copilot/auth/initiating', 'Initiating authentication...')}</p>
+            </div>
+        );
+    }
+
+    protected renderWaiting(): React.ReactNode {
+        const response = this.deviceCodeResponse!;
+        return (
+            <div className="theia-copilot-auth-waiting">
+                <p className="theia-copilot-auth-instructions">
+                    {nls.localize('theia/ai/copilot/auth/instructions',
+                        'To authorize Theia to use GitHub Copilot, visit the URL below and enter the code:')}
+                </p>
+
+                <div className="theia-copilot-auth-code-section">
+                    <div className="theia-copilot-auth-code-display">
+                        <span className="theia-copilot-auth-code">{response.user_code}</span>
+                        <button
+                            className="theia-button secondary theia-copilot-copy-button"
+                            onClick={this.handleCopyCode}
+                            title={this.copied
+                                ? nls.localize('theia/ai/copilot/auth/copied', 'Copied!')
+                                : nls.localize('theia/ai/copilot/auth/copyCode', 'Copy code')}
+                        >
+                            <span className={`codicon ${this.copied ? 'codicon-check' : 'codicon-copy'}`}></span>
+                            {nls.localizeByDefault('Copy')}
+                        </button>
+                    </div>
+                </div>
+
+                <div className="theia-copilot-auth-url-section">
+                    <button
+                        className="theia-button theia-copilot-open-url-button"
+                        onClick={this.handleOpenUrl}
+                    >
+                        <span className="codicon codicon-link-external"></span>
+                        {nls.localize('theia/ai/copilot/auth/openGitHub', 'Open GitHub')}
+                    </button>
+                    <span className="theia-copilot-auth-url">{response.verification_uri}</span>
+                </div>
+
+                <p className="theia-copilot-auth-hint">
+                    {nls.localize('theia/ai/copilot/auth/hint',
+                        'After entering the code and authorizing, click "I have authorized" below.')}
+                </p>
+
+                <div className="theia-copilot-auth-privacy">
+                    <p className="theia-copilot-auth-privacy-text">
+                        {nls.localize('theia/ai/copilot/auth/privacy',
+                            'Theia is an open-source project. We only request access to your GitHub username ' +
+                            'to connect to GitHub Copilot services — no other data is accessed or stored.')}
+                    </p>
+                    <p className="theia-copilot-auth-tos-text">
+                        {nls.localize('theia/ai/copilot/auth/tos',
+                            'By signing in, you agree to the ')}
+                        <a
+                            href="https://docs.github.com/en/site-policy/github-terms/github-terms-of-service"
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            onClick={this.handleOpenTos}
+                        >
+                            {nls.localize('theia/ai/copilot/auth/tosLink', 'GitHub Terms of Service')}
+                        </a>.
+                    </p>
+                </div>
+            </div>
+        );
+    }
+
+    protected handleOpenTos = (e: React.MouseEvent): void => {
+        e.preventDefault();
+        this.windowService.openNewWindow('https://docs.github.com/en/site-policy/github-terms/github-terms-of-service', { external: true });
+    };
+
+    protected renderPolling(): React.ReactNode {
+        return (
+            <div className="theia-copilot-auth-state">
+                <div className="theia-spin">
+                    <span className="codicon codicon-loading"></span>
+                </div>
+                <p>{nls.localize('theia/ai/copilot/auth/verifying', 'Verifying authorization...')}</p>
+            </div>
+        );
+    }
+
+    protected renderSuccess(): React.ReactNode {
+        return (
+            <div className="theia-copilot-auth-state theia-copilot-auth-success">
+                <span className="codicon codicon-check"></span>
+                <p>{nls.localize('theia/ai/copilot/auth/success', 'Successfully signed in to GitHub Copilot!')}</p>
+                <p className="theia-copilot-auth-success-hint">
+                    {nls.localize('theia/ai/copilot/auth/successHint',
+                        'If your GitHub account has access to Copilot, you can now configure Copilot language models in the ')}
+                    <a href="#" onClick={this.handleOpenAIConfig}>
+                        {nls.localize('theia/ai/copilot/auth/aiConfiguration', 'AI Configuration')}
+                    </a>.
+                </p>
+            </div>
+        );
+    }
+
+    protected handleOpenAIConfig = (e: React.MouseEvent): void => {
+        e.preventDefault();
+        this.commandService.executeCommand(OPEN_AI_CONFIG_VIEW_COMMAND);
+    };
+
+    protected handleRetry = (): void => {
+        this.initiateFlow();
+    };
+
+    protected renderError(): React.ReactNode {
+        return (
+            <div className="theia-copilot-auth-state theia-copilot-auth-error">
+                <span className="codicon codicon-error"></span>
+                <p>{this.errorMessage}</p>
+                <button
+                    className="theia-button"
+                    onClick={this.handleRetry}
+                >
+                    {nls.localizeByDefault('Try Again')}
+                </button>
+            </div>
+        );
+    }
+}

packages/ai-copilot/src/browser/copilot-command-contribution.ts

@@ -0,0 +1,93 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import { inject, injectable, postConstruct } from '@theia/core/shared/inversify';
+import { Command, CommandContribution, CommandRegistry, Disposable, DisposableCollection, PreferenceService } from '@theia/core';
+import { CopilotAuthService, CopilotAuthState } from '../common/copilot-auth-service';
+import { CopilotAuthDialog, CopilotAuthDialogProps } from './copilot-auth-dialog';
+import { COPILOT_ENTERPRISE_URL_PREF } from '../common/copilot-preferences';
+
+export namespace CopilotCommands {
+    export const SIGN_IN: Command = Command.toLocalizedCommand(
+        { id: 'copilot.signIn', label: 'Sign in to GitHub Copilot', category: 'Copilot' },
+        'theia/ai/copilot/commands/signIn',
+        'theia/ai/copilot/category'
+    );
+
+    export const SIGN_OUT: Command = Command.toLocalizedCommand(
+        { id: 'copilot.signOut', label: 'Sign out of GitHub Copilot', category: 'Copilot' },
+        'theia/ai/copilot/commands/signOut',
+        'theia/ai/copilot/category'
+    );
+}
+
+/**
+ * Command contribution for GitHub Copilot authentication commands.
+ */
+@injectable()
+export class CopilotCommandContribution implements CommandContribution, Disposable {
+
+    @inject(CopilotAuthService)
+    protected readonly authService: CopilotAuthService;
+
+    @inject(PreferenceService)
+    protected readonly preferenceService: PreferenceService;
+
+    @inject(CopilotAuthDialogProps)
+    protected readonly dialogProps: CopilotAuthDialogProps;
+
+    @inject(CopilotAuthDialog)
+    protected readonly authDialog: CopilotAuthDialog;
+
+    protected authState: CopilotAuthState = { isAuthenticated: false };
+    protected readonly toDispose = new DisposableCollection();
+
+    @postConstruct()
+    protected init(): void {
+        this.authService.getAuthState().then(state => {
+            this.authState = state;
+        });
+
+        this.toDispose.push(this.authService.onAuthStateChanged(state => {
+            this.authState = state;
+        }));
+    }
+
+    dispose(): void {
+        this.toDispose.dispose();
+    }
+
+    registerCommands(registry: CommandRegistry): void {
+        registry.registerCommand(CopilotCommands.SIGN_IN, {
+            execute: async () => {
+                const enterpriseUrl = this.preferenceService.get<string>(COPILOT_ENTERPRISE_URL_PREF);
+                this.dialogProps.enterpriseUrl = enterpriseUrl || undefined;
+                const result = await this.authDialog.open();
+                if (result) {
+                    this.authState = await this.authService.getAuthState();
+                }
+            },
+            isEnabled: () => !this.authState.isAuthenticated
+        });
+
+        registry.registerCommand(CopilotCommands.SIGN_OUT, {
+            execute: async () => {
+                await this.authService.signOut();
+            },
+            isEnabled: () => this.authState.isAuthenticated
+        });
+    }
+}

packages/ai-copilot/src/browser/copilot-frontend-application-contribution.ts

@@ -0,0 +1,89 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import { inject, injectable } from '@theia/core/shared/inversify';
+import { PreferenceService } from '@theia/core';
+import { FrontendApplicationContribution } from '@theia/core/lib/browser';
+import { CopilotLanguageModelsManager, CopilotModelDescription, COPILOT_PROVIDER_ID } from '../common';
+import { COPILOT_MODELS_PREF, COPILOT_ENTERPRISE_URL_PREF } from '../common/copilot-preferences';
+import { AICorePreferences, PREFERENCE_NAME_MAX_RETRIES } from '@theia/ai-core/lib/common/ai-core-preferences';
+
+@injectable()
+export class CopilotFrontendApplicationContribution implements FrontendApplicationContribution {
+
+    @inject(PreferenceService)
+    protected readonly preferenceService: PreferenceService;
+
+    @inject(CopilotLanguageModelsManager)
+    protected readonly manager: CopilotLanguageModelsManager;
+
+    @inject(AICorePreferences)
+    protected readonly aiCorePreferences: AICorePreferences;
+
+    protected prevModels: string[] = [];
+
+    onStart(): void {
+        this.preferenceService.ready.then(() => {
+            const models = this.preferenceService.get<string[]>(COPILOT_MODELS_PREF, []);
+            this.manager.createOrUpdateLanguageModels(...models.map((modelId: string) => this.createCopilotModelDescription(modelId)));
+            this.prevModels = [...models];
+
+            this.preferenceService.onPreferenceChanged(event => {
+                if (event.preferenceName === COPILOT_MODELS_PREF) {
+                    this.handleModelChanges(this.preferenceService.get<string[]>(COPILOT_MODELS_PREF, []));
+                } else if (event.preferenceName === COPILOT_ENTERPRISE_URL_PREF) {
+                    this.manager.refreshModelsStatus();
+                }
+            });
+
+            this.aiCorePreferences.onPreferenceChanged(event => {
+                if (event.preferenceName === PREFERENCE_NAME_MAX_RETRIES) {
+                    this.updateAllModels();
+                }
+            });
+        });
+    }
+
+    protected handleModelChanges(newModels: string[]): void {
+        const oldModels = new Set(this.prevModels);
+        const updatedModels = new Set(newModels);
+
+        const modelsToRemove = [...oldModels].filter(model => !updatedModels.has(model));
+        const modelsToAdd = [...updatedModels].filter(model => !oldModels.has(model));
+
+        this.manager.removeLanguageModels(...modelsToRemove.map(model => `${COPILOT_PROVIDER_ID}/${model}`));
+        this.manager.createOrUpdateLanguageModels(...modelsToAdd.map((modelId: string) => this.createCopilotModelDescription(modelId)));
+        this.prevModels = newModels;
+    }
+
+    protected updateAllModels(): void {
+        const models = this.preferenceService.get<string[]>(COPILOT_MODELS_PREF, []);
+        this.manager.createOrUpdateLanguageModels(...models.map((modelId: string) => this.createCopilotModelDescription(modelId)));
+    }
+
+    protected createCopilotModelDescription(modelId: string): CopilotModelDescription {
+        const id = `${COPILOT_PROVIDER_ID}/${modelId}`;
+        const maxRetries = this.aiCorePreferences.get(PREFERENCE_NAME_MAX_RETRIES) ?? 3;
+
+        return {
+            id,
+            model: modelId,
+            enableStreaming: true,
+            supportsStructuredOutput: true,
+            maxRetries
+        };
+    }
+}

packages/ai-copilot/src/browser/copilot-frontend-module.ts

@@ -0,0 +1,86 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import '../../src/browser/style/index.css';
+
+import { ContainerModule } from '@theia/core/shared/inversify';
+import { CommandContribution, Emitter, Event, nls, PreferenceContribution } from '@theia/core';
+import {
+    FrontendApplicationContribution,
+    RemoteConnectionProvider,
+    ServiceConnectionProvider
+} from '@theia/core/lib/browser';
+import {
+    CopilotLanguageModelsManager,
+    COPILOT_LANGUAGE_MODELS_MANAGER_PATH,
+    CopilotAuthService,
+    COPILOT_AUTH_SERVICE_PATH,
+    CopilotAuthServiceClient,
+    CopilotAuthState
+} from '../common';
+import { CopilotPreferencesSchema } from '../common/copilot-preferences';
+import { CopilotFrontendApplicationContribution } from './copilot-frontend-application-contribution';
+import { CopilotCommandContribution } from './copilot-command-contribution';
+import { CopilotStatusBarContribution } from './copilot-status-bar-contribution';
+import { CopilotAuthDialog, CopilotAuthDialogProps } from './copilot-auth-dialog';
+
+class CopilotAuthServiceClientImpl implements CopilotAuthServiceClient {
+    protected readonly onAuthStateChangedEmitter = new Emitter<CopilotAuthState>();
+    readonly onAuthStateChangedEvent: Event<CopilotAuthState> = this.onAuthStateChangedEmitter.event;
+    onAuthStateChanged(state: CopilotAuthState): void {
+        this.onAuthStateChangedEmitter.fire(state);
+    }
+}
+
+export default new ContainerModule(bind => {
+    bind(PreferenceContribution).toConstantValue({ schema: CopilotPreferencesSchema });
+
+    bind(CopilotCommandContribution).toSelf().inSingletonScope();
+    bind(CommandContribution).toService(CopilotCommandContribution);
+
+    bind(CopilotStatusBarContribution).toSelf().inSingletonScope();
+    bind(FrontendApplicationContribution).toService(CopilotStatusBarContribution);
+
+    bind(CopilotAuthDialogProps).toConstantValue({
+        title: nls.localize('theia/ai/copilot/commands/signIn', 'Sign in to GitHub Copilot')
+    });
+    bind(CopilotAuthDialog).toSelf().inSingletonScope();
+
+    bind(CopilotFrontendApplicationContribution).toSelf().inSingletonScope();
+    bind(FrontendApplicationContribution).toService(CopilotFrontendApplicationContribution);
+
+    bind(CopilotAuthServiceClientImpl).toConstantValue(new CopilotAuthServiceClientImpl());
+    bind(CopilotAuthServiceClient).toService(CopilotAuthServiceClientImpl);
+
+    bind(CopilotLanguageModelsManager).toDynamicValue(ctx => {
+        const provider = ctx.container.get<ServiceConnectionProvider>(RemoteConnectionProvider);
+        return provider.createProxy<CopilotLanguageModelsManager>(COPILOT_LANGUAGE_MODELS_MANAGER_PATH);
+    }).inSingletonScope();
+
+    bind(CopilotAuthService).toDynamicValue(ctx => {
+        const provider = ctx.container.get<ServiceConnectionProvider>(RemoteConnectionProvider);
+        const clientImpl = ctx.container.get(CopilotAuthServiceClientImpl);
+        const proxy = provider.createProxy<CopilotAuthService>(COPILOT_AUTH_SERVICE_PATH, clientImpl);
+        return new Proxy(proxy, {
+            get(target: CopilotAuthService, prop: string | symbol, receiver: unknown): unknown {
+                if (prop === 'onAuthStateChanged') {
+                    return clientImpl.onAuthStateChangedEvent;
+                }
+                return Reflect.get(target, prop, receiver);
+            }
+        }) as CopilotAuthService;
+    }).inSingletonScope();
+});

packages/ai-copilot/src/browser/copilot-status-bar-contribution.ts

@@ -0,0 +1,88 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import { inject, injectable, postConstruct } from '@theia/core/shared/inversify';
+import { FrontendApplicationContribution } from '@theia/core/lib/browser';
+import { StatusBar, StatusBarAlignment } from '@theia/core/lib/browser/status-bar/status-bar-types';
+import { Disposable, DisposableCollection, nls } from '@theia/core';
+import { CopilotAuthService, CopilotAuthState } from '../common/copilot-auth-service';
+import { CopilotCommands } from './copilot-command-contribution';
+
+const COPILOT_STATUS_BAR_ID = 'copilot-auth-status';
+
+/**
+ * Frontend contribution that displays GitHub Copilot authentication status in the status bar.
+ */
+@injectable()
+export class CopilotStatusBarContribution implements FrontendApplicationContribution, Disposable {
+
+    @inject(StatusBar)
+    protected readonly statusBar: StatusBar;
+
+    @inject(CopilotAuthService)
+    protected readonly authService: CopilotAuthService;
+
+    protected authState: CopilotAuthState = { isAuthenticated: false };
+    protected readonly toDispose = new DisposableCollection();
+
+    @postConstruct()
+    protected init(): void {
+        this.toDispose.push(this.authService.onAuthStateChanged(state => {
+            this.authState = state;
+            this.updateStatusBar();
+        }));
+    }
+
+    dispose(): void {
+        this.toDispose.dispose();
+    }
+
+    onStart(): void {
+        this.authService.getAuthState().then(state => {
+            this.authState = state;
+            this.updateStatusBar();
+        });
+    }
+
+    protected updateStatusBar(): void {
+        const isAuthenticated = this.authState.isAuthenticated;
+
+        let text: string;
+        let tooltip: string;
+        let command: string;
+
+        if (isAuthenticated) {
+            const accountLabel = this.authState.accountLabel ?? 'GitHub';
+            text = `$(github) ${accountLabel}`;
+            tooltip = nls.localize('theia/ai/copilot/statusBar/signedIn',
+                'Signed in to GitHub Copilot as {0}. Click to sign out.', accountLabel);
+            command = CopilotCommands.SIGN_OUT.id;
+        } else {
+            text = '$(github) Copilot';
+            tooltip = nls.localize('theia/ai/copilot/statusBar/signedOut',
+                'Not signed in to GitHub Copilot. Click to sign in.');
+            command = CopilotCommands.SIGN_IN.id;
+        }
+
+        this.statusBar.setElement(COPILOT_STATUS_BAR_ID, {
+            text,
+            tooltip,
+            alignment: StatusBarAlignment.RIGHT,
+            priority: 100,
+            command
+        });
+    }
+}

packages/ai-copilot/src/browser/index.ts

@@ -0,0 +1,20 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+export * from './copilot-auth-dialog';
+export * from './copilot-command-contribution';
+export * from './copilot-status-bar-contribution';
+export * from './copilot-frontend-application-contribution';

packages/ai-copilot/src/browser/style/index.css

@@ -0,0 +1,167 @@
+/* *****************************************************************************
+ * Copyright (C) 2026 EclipseSource GmbH.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * This Source Code may also be made available under the following Secondary
+ * Licenses when the conditions for such availability set forth in the Eclipse
+ * Public License v. 2.0 are satisfied: GNU General Public License, version 2
+ * with the GNU Classpath Exception which is available at
+ * https://www.gnu.org/software/classpath/license.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+ **************************************************************************** */
+
+.theia-copilot-auth-dialog-content {
+  padding: 16px;
+  min-width: 400px;
+}
+
+.theia-copilot-auth-state {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 12px;
+  padding: 24px;
+}
+
+.theia-copilot-auth-state .theia-spin {
+  font-size: 32px;
+}
+
+.theia-copilot-auth-success .codicon-check {
+  font-size: 48px;
+  color: var(--theia-successBackground);
+}
+
+.theia-copilot-auth-error .codicon-error {
+  font-size: 48px;
+  color: var(--theia-errorForeground);
+}
+
+.theia-copilot-auth-waiting {
+  display: flex;
+  flex-direction: column;
+  gap: 16px;
+}
+
+.theia-copilot-auth-instructions {
+  margin: 0;
+  line-height: 1.5;
+}
+
+.theia-copilot-auth-code-section {
+  display: flex;
+  justify-content: center;
+}
+
+.theia-copilot-auth-code-display {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+  padding: 12px 16px;
+  background: var(--theia-editor-background);
+  border-radius: 4px;
+  border: 1px solid var(--theia-panel-border);
+}
+
+.theia-copilot-auth-code {
+  font-family: var(--theia-code-font-family);
+  font-size: 24px;
+  font-weight: bold;
+  letter-spacing: 2px;
+  color: var(--theia-textLink-foreground);
+}
+
+.theia-copilot-copy-button {
+  display: flex;
+  align-items: center;
+  gap: 4px;
+  padding: 4px 8px;
+}
+
+.theia-copilot-auth-url-section {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+  justify-content: center;
+}
+
+.theia-copilot-open-url-button {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+}
+
+.theia-copilot-auth-url {
+  font-family: var(--theia-code-font-family);
+  font-size: 12px;
+  color: var(--theia-descriptionForeground);
+}
+
+.theia-copilot-auth-hint {
+  margin: 0;
+  font-size: 12px;
+  color: var(--theia-descriptionForeground);
+  text-align: center;
+}
+
+.theia-copilot-auth-privacy {
+  margin-top: 8px;
+  padding-top: 12px;
+  border-top: 1px solid var(--theia-panel-border);
+}
+
+.theia-copilot-auth-privacy-text,
+.theia-copilot-auth-tos-text {
+  margin: 0 0 8px 0;
+  font-size: 11px;
+  color: var(--theia-descriptionForeground);
+  line-height: 1.4;
+}
+
+.theia-copilot-auth-tos-text:last-child {
+  margin-bottom: 0;
+}
+
+.theia-copilot-auth-privacy a {
+  color: var(--theia-textLink-foreground);
+  text-decoration: none;
+}
+
+.theia-copilot-auth-privacy a:hover {
+  text-decoration: underline;
+}
+
+.theia-copilot-auth-success-hint {
+  margin: 8px 0 0 0;
+  font-size: 12px;
+  color: var(--theia-descriptionForeground);
+  text-align: center;
+}
+
+.theia-copilot-auth-success-hint a {
+  color: var(--theia-textLink-foreground);
+  text-decoration: none;
+  cursor: pointer;
+}
+
+.theia-copilot-auth-success-hint a:hover {
+  text-decoration: underline;
+}
+
+/* Spinning animation for loading indicator */
+.theia-spin .codicon {
+  animation: spin 1s linear infinite;
+}
+
+@keyframes spin {
+  from {
+    transform: rotate(0deg);
+  }
+  to {
+    transform: rotate(360deg);
+  }
+}

packages/ai-copilot/src/common/copilot-auth-service.ts

@@ -0,0 +1,103 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import { Event } from '@theia/core';
+
+export const COPILOT_AUTH_SERVICE_PATH = '/services/copilot/auth';
+export const CopilotAuthService = Symbol('CopilotAuthService');
+export const CopilotAuthServiceClient = Symbol('CopilotAuthServiceClient');
+
+/**
+ * Response from GitHub's device code endpoint.
+ */
+export interface DeviceCodeResponse {
+    /** URL where user should enter the code (e.g., https://github.com/login/device) */
+    verification_uri: string;
+    /** Code to display to the user (e.g., XXXX-XXXX) */
+    user_code: string;
+    /** Device code used for polling */
+    device_code: string;
+    /** Polling interval in seconds */
+    interval: number;
+    /** Expiration time in seconds */
+    expires_in: number;
+}
+
+/**
+ * Current authentication state.
+ */
+export interface CopilotAuthState {
+    /** Whether the user is authenticated */
+    isAuthenticated: boolean;
+    /** GitHub username if authenticated */
+    accountLabel?: string;
+    /** GitHub Enterprise URL if using enterprise */
+    enterpriseUrl?: string;
+}
+
+/**
+ * Client interface for receiving auth state change notifications.
+ */
+export interface CopilotAuthServiceClient {
+    onAuthStateChanged(state: CopilotAuthState): void;
+}
+
+/**
+ * Service for handling GitHub Copilot OAuth Device Flow authentication.
+ */
+export interface CopilotAuthService {
+    /**
+     * Initiates the OAuth Device Flow.
+     * Returns device code information for the UI to display.
+     * @param enterpriseUrl Optional GitHub Enterprise domain
+     */
+    initiateDeviceFlow(enterpriseUrl?: string): Promise<DeviceCodeResponse>;
+
+    /**
+     * Polls for the access token after user authorizes.
+     * @param deviceCode The device code from initiateDeviceFlow
+     * @param interval Polling interval in seconds
+     * @param enterpriseUrl Optional GitHub Enterprise domain
+     * @returns true if authentication succeeded, false if expired/denied
+     */
+    pollForToken(deviceCode: string, interval: number, enterpriseUrl?: string): Promise<boolean>;
+
+    /**
+     * Get the current authentication state.
+     */
+    getAuthState(): Promise<CopilotAuthState>;
+
+    /**
+     * Get the access token for API calls.
+     * @returns The access token or undefined if not authenticated
+     */
+    getAccessToken(): Promise<string | undefined>;
+
+    /**
+     * Sign out and clear stored credentials.
+     */
+    signOut(): Promise<void>;
+
+    /**
+     * Set the client to receive auth state change notifications.
+     */
+    setClient(client: CopilotAuthServiceClient | undefined): void;
+
+    /**
+     * Event fired when authentication state changes.
+     */
+    readonly onAuthStateChanged: Event<CopilotAuthState>;
+}

packages/ai-copilot/src/common/copilot-language-models-manager.ts

@@ -0,0 +1,59 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+export const COPILOT_LANGUAGE_MODELS_MANAGER_PATH = '/services/copilot/language-model-manager';
+export const CopilotLanguageModelsManager = Symbol('CopilotLanguageModelsManager');
+
+export const COPILOT_PROVIDER_ID = 'copilot';
+
+export interface CopilotModelDescription {
+    /**
+     * The identifier of the model which will be shown in the UI.
+     * Format: copilot/{modelName}
+     */
+    id: string;
+    /**
+     * The model ID as used by the Copilot API (e.g., 'gpt-4o', 'claude-3.5-sonnet').
+     */
+    model: string;
+    /**
+     * Indicate whether the streaming API shall be used.
+     */
+    enableStreaming: boolean;
+    /**
+     * Flag to configure whether the model supports structured output.
+     */
+    supportsStructuredOutput: boolean;
+    /**
+     * Maximum number of retry attempts when a request fails.
+     */
+    maxRetries: number;
+}
+
+export interface CopilotLanguageModelsManager {
+    /**
+     * Create or update language models in the registry.
+     */
+    createOrUpdateLanguageModels(...models: CopilotModelDescription[]): Promise<void>;
+    /**
+     * Remove language models from the registry.
+     */
+    removeLanguageModels(...modelIds: string[]): void;
+    /**
+     * Refresh the status of all Copilot models (e.g., after authentication state changes).
+     */
+    refreshModelsStatus(): Promise<void>;
+}

packages/ai-copilot/src/common/copilot-preferences.ts

@@ -0,0 +1,53 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import { AI_CORE_PREFERENCES_TITLE } from '@theia/ai-core/lib/common/ai-core-preferences';
+import { nls, PreferenceSchema } from '@theia/core';
+
+export const COPILOT_MODELS_PREF = 'ai-features.copilot.models';
+export const COPILOT_ENTERPRISE_URL_PREF = 'ai-features.copilot.enterpriseUrl';
+
+export const CopilotPreferencesSchema: PreferenceSchema = {
+    properties: {
+        [COPILOT_MODELS_PREF]: {
+            type: 'array',
+            description: nls.localize('theia/ai/copilot/models/description',
+                'GitHub Copilot models to use. Available models depend on your Copilot subscription.'),
+            title: AI_CORE_PREFERENCES_TITLE,
+            // https://models.dev/?search=copilot
+            default: [
+                'claude-haiku-4.5',
+                'claude-sonnet-4.5',
+                'claude-opus-4.5',
+                'gemini-2.5-pro',
+                'gpt-4.1',
+                'gpt-4o',
+                'gpt-5-mini',
+                'gpt-5.2',
+            ],
+            items: {
+                type: 'string'
+            }
+        },
+        [COPILOT_ENTERPRISE_URL_PREF]: {
+            type: 'string',
+            markdownDescription: nls.localize('theia/ai/copilot/enterpriseUrl/mdDescription',
+                'GitHub Enterprise domain for Copilot API (e.g., `github.mycompany.com`). Leave empty for GitHub.com.'),
+            title: AI_CORE_PREFERENCES_TITLE,
+            default: ''
+        }
+    }
+};

packages/ai-copilot/src/common/index.ts

@@ -0,0 +1,19 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+export * from './copilot-language-models-manager';
+export * from './copilot-auth-service';
+export * from './copilot-preferences';

packages/ai-copilot/src/node/copilot-auth-service-impl.ts

@@ -0,0 +1,274 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import { inject, injectable } from '@theia/core/shared/inversify';
+import { Emitter, Event } from '@theia/core';
+import { KeyStoreService } from '@theia/core/lib/common/key-store';
+import {
+    CopilotAuthService,
+    CopilotAuthServiceClient,
+    CopilotAuthState,
+    DeviceCodeResponse
+} from '../common/copilot-auth-service';
+
+const COPILOT_CLIENT_ID = 'Iv23ctNZvWb5IGBKdyPY';
+const COPILOT_SCOPE = 'read:user';
+const COPILOT_GRANT_TYPE = 'urn:ietf:params:oauth:grant-type:device_code';
+const KEYSTORE_SERVICE = 'theia-copilot-auth';
+const KEYSTORE_ACCOUNT = 'github-copilot';
+const USER_AGENT = 'Theia-Copilot/1.0.0';
+
+/**
+ * Maximum number of polling attempts for token retrieval.
+ * With a default 5-second interval, this allows approximately 5 minutes of polling.
+ */
+const MAX_POLLING_ATTEMPTS = 60;
+
+interface StoredCredentials {
+    accessToken: string;
+    accountLabel?: string;
+    enterpriseUrl?: string;
+}
+
+/**
+ * Backend implementation of the GitHub Copilot OAuth Device Flow authentication service.
+ * Handles device code generation, token polling, and credential storage.
+ */
+@injectable()
+export class CopilotAuthServiceImpl implements CopilotAuthService {
+
+    @inject(KeyStoreService)
+    protected readonly keyStoreService: KeyStoreService;
+
+    protected client: CopilotAuthServiceClient | undefined;
+    protected cachedState: CopilotAuthState | undefined;
+
+    protected readonly onAuthStateChangedEmitter = new Emitter<CopilotAuthState>();
+    readonly onAuthStateChanged: Event<CopilotAuthState> = this.onAuthStateChangedEmitter.event;
+
+    setClient(client: CopilotAuthServiceClient | undefined): void {
+        this.client = client;
+    }
+
+    protected getOAuthEndpoints(enterpriseUrl?: string): { deviceCodeUrl: string; accessTokenUrl: string } {
+        if (enterpriseUrl) {
+            const domain = enterpriseUrl
+                .replace(/^https?:\/\//, '')
+                .replace(/\/$/, '');
+            return {
+                deviceCodeUrl: `https://${domain}/login/device/code`,
+                accessTokenUrl: `https://${domain}/login/oauth/access_token`
+            };
+        }
+        return {
+            deviceCodeUrl: 'https://github.com/login/device/code',
+            accessTokenUrl: 'https://github.com/login/oauth/access_token'
+        };
+    }
+
+    async initiateDeviceFlow(enterpriseUrl?: string): Promise<DeviceCodeResponse> {
+        const endpoints = this.getOAuthEndpoints(enterpriseUrl);
+
+        const response = await fetch(endpoints.deviceCodeUrl, {
+            method: 'POST',
+            headers: {
+                'Accept': 'application/json',
+                'Content-Type': 'application/json',
+                'User-Agent': USER_AGENT
+            },
+            body: JSON.stringify({
+                client_id: COPILOT_CLIENT_ID,
+                scope: COPILOT_SCOPE
+            })
+        });
+
+        if (!response.ok) {
+            const errorText = await response.text();
+            throw new Error(`Failed to initiate device authorization: ${response.status} - ${errorText}`);
+        }
+
+        const data = await response.json() as DeviceCodeResponse;
+        return data;
+    }
+
+    async pollForToken(deviceCode: string, interval: number, enterpriseUrl?: string): Promise<boolean> {
+        const endpoints = this.getOAuthEndpoints(enterpriseUrl);
+        let attempts = 0;
+
+        while (attempts < MAX_POLLING_ATTEMPTS) {
+            await this.delay(interval * 1000);
+            attempts++;
+
+            const response = await fetch(endpoints.accessTokenUrl, {
+                method: 'POST',
+                headers: {
+                    'Accept': 'application/json',
+                    'Content-Type': 'application/json',
+                    'User-Agent': USER_AGENT
+                },
+                body: JSON.stringify({
+                    client_id: COPILOT_CLIENT_ID,
+                    device_code: deviceCode,
+                    grant_type: COPILOT_GRANT_TYPE
+                })
+            });
+
+            if (!response.ok) {
+                console.error(`Token request failed: ${response.status}`);
+                continue;
+            }
+
+            const data = await response.json() as {
+                access_token?: string;
+                error?: string;
+                error_description?: string;
+            };
+
+            if (data.access_token) {
+                // Get user info for account label
+                const accountLabel = await this.fetchAccountLabel(data.access_token, enterpriseUrl);
+
+                // Store credentials
+                const credentials: StoredCredentials = {
+                    accessToken: data.access_token,
+                    accountLabel,
+                    enterpriseUrl
+                };
+
+                await this.keyStoreService.setPassword(
+                    KEYSTORE_SERVICE,
+                    KEYSTORE_ACCOUNT,
+                    JSON.stringify(credentials)
+                );
+
+                // Update cached state and notify
+                const newState: CopilotAuthState = {
+                    isAuthenticated: true,
+                    accountLabel,
+                    enterpriseUrl
+                };
+                this.updateAuthState(newState);
+
+                return true;
+            }
+
+            if (data.error === 'authorization_pending') {
+                // User hasn't authorized yet, continue polling
+                continue;
+            }
+
+            if (data.error === 'slow_down') {
+                // Increase polling interval
+                interval += 5;
+                continue;
+            }
+
+            if (data.error === 'expired_token' || data.error === 'access_denied') {
+                console.error(`Authorization failed: ${data.error} - ${data.error_description}`);
+                return false;
+            }
+
+            if (data.error) {
+                console.error(`Unexpected error: ${data.error} - ${data.error_description}`);
+                return false;
+            }
+        }
+
+        return false;
+    }
+
+    protected async fetchAccountLabel(accessToken: string, enterpriseUrl?: string): Promise<string | undefined> {
+        try {
+            const apiBaseUrl = enterpriseUrl
+                ? `https://${enterpriseUrl.replace(/^https?:\/\//, '').replace(/\/$/, '')}/api/v3`
+                : 'https://api.github.com';
+
+            const response = await fetch(`${apiBaseUrl}/user`, {
+                headers: {
+                    'Authorization': `Bearer ${accessToken}`,
+                    'User-Agent': USER_AGENT,
+                    'Accept': 'application/vnd.github.v3+json'
+                }
+            });
+
+            if (response.ok) {
+                const userData = await response.json() as { login?: string };
+                return userData.login;
+            }
+        } catch (error) {
+            console.warn('Failed to fetch GitHub user info:', error);
+        }
+        return undefined;
+    }
+
+    async getAuthState(): Promise<CopilotAuthState> {
+        if (this.cachedState) {
+            return this.cachedState;
+        }
+
+        try {
+            const stored = await this.keyStoreService.getPassword(KEYSTORE_SERVICE, KEYSTORE_ACCOUNT);
+            if (stored) {
+                const credentials: StoredCredentials = JSON.parse(stored);
+                this.cachedState = {
+                    isAuthenticated: true,
+                    accountLabel: credentials.accountLabel,
+                    enterpriseUrl: credentials.enterpriseUrl
+                };
+                return this.cachedState;
+            }
+        } catch (error) {
+            console.warn('Failed to retrieve Copilot credentials:', error);
+        }
+
+        this.cachedState = { isAuthenticated: false };
+        return this.cachedState;
+    }
+
+    async getAccessToken(): Promise<string | undefined> {
+        try {
+            const stored = await this.keyStoreService.getPassword(KEYSTORE_SERVICE, KEYSTORE_ACCOUNT);
+            if (stored) {
+                const credentials: StoredCredentials = JSON.parse(stored);
+                return credentials.accessToken;
+            }
+        } catch (error) {
+            console.warn('Failed to retrieve Copilot access token:', error);
+        }
+        return undefined;
+    }
+
+    async signOut(): Promise<void> {
+        try {
+            await this.keyStoreService.deletePassword(KEYSTORE_SERVICE, KEYSTORE_ACCOUNT);
+        } catch (error) {
+            console.warn('Failed to delete Copilot credentials:', error);
+        }
+
+        const newState: CopilotAuthState = { isAuthenticated: false };
+        this.updateAuthState(newState);
+    }
+
+    protected updateAuthState(state: CopilotAuthState): void {
+        this.cachedState = state;
+        this.onAuthStateChangedEmitter.fire(state);
+        this.client?.onAuthStateChanged(state);
+    }
+
+    protected delay(ms: number): Promise<void> {
+        return new Promise(resolve => setTimeout(resolve, ms));
+    }
+}

packages/ai-copilot/src/node/copilot-backend-module.ts

@@ -0,0 +1,58 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import { ContainerModule } from '@theia/core/shared/inversify';
+import { ConnectionHandler, RpcConnectionHandler } from '@theia/core';
+import { ConnectionContainerModule } from '@theia/core/lib/node/messaging/connection-container-module';
+import {
+    CopilotLanguageModelsManager,
+    COPILOT_LANGUAGE_MODELS_MANAGER_PATH,
+    CopilotAuthService,
+    COPILOT_AUTH_SERVICE_PATH,
+    CopilotAuthServiceClient
+} from '../common';
+import { CopilotLanguageModelsManagerImpl } from './copilot-language-models-manager-impl';
+import { CopilotAuthServiceImpl } from './copilot-auth-service-impl';
+
+const copilotConnectionModule = ConnectionContainerModule.create(({ bind }) => {
+    bind(CopilotAuthServiceImpl).toSelf().inSingletonScope();
+    bind(CopilotAuthService).toService(CopilotAuthServiceImpl);
+
+    bind(CopilotLanguageModelsManagerImpl).toSelf().inSingletonScope();
+    bind(CopilotLanguageModelsManager).toService(CopilotLanguageModelsManagerImpl);
+
+    bind(ConnectionHandler).toDynamicValue(ctx =>
+        new RpcConnectionHandler<CopilotAuthServiceClient>(
+            COPILOT_AUTH_SERVICE_PATH,
+            client => {
+                const authService = ctx.container.get<CopilotAuthServiceImpl>(CopilotAuthService);
+                authService.setClient(client);
+                return authService;
+            }
+        )
+    ).inSingletonScope();
+
+    bind(ConnectionHandler).toDynamicValue(ctx =>
+        new RpcConnectionHandler(
+            COPILOT_LANGUAGE_MODELS_MANAGER_PATH,
+            () => ctx.container.get(CopilotLanguageModelsManager)
+        )
+    ).inSingletonScope();
+});
+
+export default new ContainerModule(bind => {
+    bind(ConnectionContainerModule).toConstantValue(copilotConnectionModule);
+});

packages/ai-copilot/src/node/copilot-language-model.ts

@@ -0,0 +1,262 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import {
+    ImageContent,
+    LanguageModel,
+    LanguageModelMessage,
+    LanguageModelParsedResponse,
+    LanguageModelRequest,
+    LanguageModelResponse,
+    LanguageModelStatus,
+    LanguageModelTextResponse,
+    TokenUsageService,
+    UserRequest
+} from '@theia/ai-core';
+import { CancellationToken } from '@theia/core';
+import OpenAI from 'openai';
+import { RunnableToolFunctionWithoutParse } from 'openai/lib/RunnableFunction';
+import { ChatCompletionMessageParam } from 'openai/resources';
+import { StreamingAsyncIterator } from '@theia/ai-openai/lib/node/openai-streaming-iterator';
+import { COPILOT_PROVIDER_ID } from '../common';
+import type { RunnerOptions } from 'openai/lib/AbstractChatCompletionRunner';
+import type { ChatCompletionStream } from 'openai/lib/ChatCompletionStream';
+
+const COPILOT_API_BASE_URL = 'https://api.githubcopilot.com';
+const USER_AGENT = 'Theia-Copilot/1.0.0';
+
+/**
+ * Language model implementation for GitHub Copilot.
+ * Uses the OpenAI SDK to communicate with the Copilot API.
+ */
+export class CopilotLanguageModel implements LanguageModel {
+
+    protected runnerOptions: RunnerOptions = {
+        maxChatCompletions: 100
+    };
+
+    constructor(
+        public readonly id: string,
+        public model: string,
+        public status: LanguageModelStatus,
+        public enableStreaming: boolean,
+        public supportsStructuredOutput: boolean,
+        public maxRetries: number,
+        protected readonly accessTokenProvider: () => Promise<string | undefined>,
+        protected readonly enterpriseUrlProvider: () => string | undefined,
+        protected readonly tokenUsageService?: TokenUsageService
+    ) { }
+
+    protected getSettings(request: LanguageModelRequest): Record<string, unknown> {
+        return request.settings ?? {};
+    }
+
+    async request(request: UserRequest, cancellationToken?: CancellationToken): Promise<LanguageModelResponse> {
+        const openai = await this.initializeCopilotClient();
+
+        if (request.response_format?.type === 'json_schema' && this.supportsStructuredOutput) {
+            return this.handleStructuredOutputRequest(openai, request);
+        }
+
+        const settings = this.getSettings(request);
+
+        if (!this.enableStreaming || (typeof settings.stream === 'boolean' && !settings.stream)) {
+            return this.handleNonStreamingRequest(openai, request);
+        }
+
+        if (cancellationToken?.isCancellationRequested) {
+            return { text: '' };
+        }
+
+        if (this.id.startsWith(`${COPILOT_PROVIDER_ID}/`)) {
+            settings['stream_options'] = { include_usage: true };
+        }
+
+        let runner: ChatCompletionStream;
+        const tools = this.createTools(request);
+
+        if (tools) {
+            runner = openai.chat.completions.runTools({
+                model: this.model,
+                messages: this.processMessages(request.messages),
+                stream: true,
+                tools: tools,
+                tool_choice: 'auto',
+                ...settings
+            }, {
+                ...this.runnerOptions,
+                maxRetries: this.maxRetries
+            });
+        } else {
+            runner = openai.chat.completions.stream({
+                model: this.model,
+                messages: this.processMessages(request.messages),
+                stream: true,
+                ...settings
+            });
+        }
+
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        return { stream: new StreamingAsyncIterator(runner as any, request.requestId, cancellationToken, this.tokenUsageService, this.id) };
+    }
+
+    protected async handleNonStreamingRequest(openai: OpenAI, request: UserRequest): Promise<LanguageModelTextResponse> {
+        const settings = this.getSettings(request);
+        const response = await openai.chat.completions.create({
+            model: this.model,
+            messages: this.processMessages(request.messages),
+            ...settings
+        });
+
+        const message = response.choices[0].message;
+
+        if (this.tokenUsageService && response.usage) {
+            await this.tokenUsageService.recordTokenUsage(
+                this.id,
+                {
+                    inputTokens: response.usage.prompt_tokens,
+                    outputTokens: response.usage.completion_tokens,
+                    requestId: request.requestId
+                }
+            );
+        }
+
+        return {
+            text: message.content ?? ''
+        };
+    }
+
+    protected async handleStructuredOutputRequest(openai: OpenAI, request: UserRequest): Promise<LanguageModelParsedResponse> {
+        const settings = this.getSettings(request);
+        const result = await openai.chat.completions.parse({
+            model: this.model,
+            messages: this.processMessages(request.messages),
+            response_format: request.response_format,
+            ...settings
+        });
+
+        const message = result.choices[0].message;
+        if (message.refusal || message.parsed === undefined) {
+            console.error('Error in Copilot chat completion:', JSON.stringify(message));
+        }
+
+        if (this.tokenUsageService && result.usage) {
+            await this.tokenUsageService.recordTokenUsage(
+                this.id,
+                {
+                    inputTokens: result.usage.prompt_tokens,
+                    outputTokens: result.usage.completion_tokens,
+                    requestId: request.requestId
+                }
+            );
+        }
+
+        return {
+            content: message.content ?? '',
+            parsed: message.parsed
+        };
+    }
+
+    protected createTools(request: LanguageModelRequest): RunnableToolFunctionWithoutParse[] | undefined {
+        return request.tools?.map(tool => ({
+            type: 'function',
+            function: {
+                name: tool.name,
+                description: tool.description,
+                parameters: tool.parameters,
+                function: (args_string: string) => tool.handler(args_string)
+            }
+        } as RunnableToolFunctionWithoutParse));
+    }
+
+    protected async initializeCopilotClient(): Promise<OpenAI> {
+        const accessToken = await this.accessTokenProvider();
+        if (!accessToken) {
+            throw new Error('Not authenticated with GitHub Copilot. Please sign in first.');
+        }
+
+        const enterpriseUrl = this.enterpriseUrlProvider();
+        const baseURL = enterpriseUrl
+            ? `https://copilot-api.${enterpriseUrl.replace(/^https?:\/\//, '').replace(/\/$/, '')}`
+            : COPILOT_API_BASE_URL;
+
+        return new OpenAI({
+            apiKey: accessToken,
+            baseURL,
+            defaultHeaders: {
+                'User-Agent': USER_AGENT,
+                'Openai-Intent': 'conversation-edits',
+                'X-Initiator': 'user'
+            }
+        });
+    }
+
+    protected processMessages(messages: LanguageModelMessage[]): ChatCompletionMessageParam[] {
+        return messages.filter(m => m.type !== 'thinking').map(m => this.toOpenAIMessage(m));
+    }
+
+    protected toOpenAIMessage(message: LanguageModelMessage): ChatCompletionMessageParam {
+        if (LanguageModelMessage.isTextMessage(message)) {
+            return {
+                role: this.toOpenAiRole(message),
+                content: message.text
+            };
+        }
+        if (LanguageModelMessage.isToolUseMessage(message)) {
+            return {
+                role: 'assistant',
+                tool_calls: [{
+                    id: message.id,
+                    function: {
+                        name: message.name,
+                        arguments: JSON.stringify(message.input)
+                    },
+                    type: 'function'
+                }]
+            };
+        }
+        if (LanguageModelMessage.isToolResultMessage(message)) {
+            return {
+                role: 'tool',
+                tool_call_id: message.tool_use_id,
+                content: typeof message.content === 'string' ? message.content : JSON.stringify(message.content)
+            };
+        }
+        if (LanguageModelMessage.isImageMessage(message) && message.actor === 'user') {
+            return {
+                role: 'user',
+                content: [{
+                    type: 'image_url',
+                    image_url: {
+                        url: ImageContent.isBase64(message.image)
+                            ? `data:${message.image.mimeType};base64,${message.image.base64data}`
+                            : message.image.url
+                    }
+                }]
+            };
+        }
+        throw new Error(`Unknown message type: '${JSON.stringify(message)}'`);
+    }
+
+    protected toOpenAiRole(message: LanguageModelMessage): 'developer' | 'user' | 'assistant' | 'system' {
+        if (message.actor === 'system') {
+            return 'developer';
+        } else if (message.actor === 'ai') {
+            return 'assistant';
+        }
+        return 'user';
+    }
+}

packages/ai-copilot/src/node/copilot-language-models-manager-impl.ts

@@ -0,0 +1,118 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import { LanguageModelRegistry, LanguageModelStatus, TokenUsageService } from '@theia/ai-core';
+import { Disposable, DisposableCollection } from '@theia/core';
+import { inject, injectable, postConstruct } from '@theia/core/shared/inversify';
+import { CopilotLanguageModelsManager, CopilotModelDescription, COPILOT_PROVIDER_ID } from '../common';
+import { CopilotLanguageModel } from './copilot-language-model';
+import { CopilotAuthServiceImpl } from './copilot-auth-service-impl';
+
+/**
+ * Backend implementation of the Copilot language models manager.
+ * Manages registration and lifecycle of Copilot language models in the AI language model registry.
+ */
+@injectable()
+export class CopilotLanguageModelsManagerImpl implements CopilotLanguageModelsManager, Disposable {
+
+    @inject(LanguageModelRegistry)
+    protected readonly languageModelRegistry: LanguageModelRegistry;
+
+    @inject(TokenUsageService)
+    protected readonly tokenUsageService: TokenUsageService;
+
+    @inject(CopilotAuthServiceImpl)
+    protected readonly authService: CopilotAuthServiceImpl;
+
+    protected enterpriseUrl: string | undefined;
+    protected readonly toDispose = new DisposableCollection();
+
+    @postConstruct()
+    protected init(): void {
+        this.toDispose.push(this.authService.onAuthStateChanged(() => {
+            this.refreshModelsStatus();
+        }));
+    }
+
+    dispose(): void {
+        this.toDispose.dispose();
+    }
+
+    setEnterpriseUrl(url: string | undefined): void {
+        this.enterpriseUrl = url;
+    }
+
+    protected async calculateStatus(): Promise<LanguageModelStatus> {
+        const authState = await this.authService.getAuthState();
+        if (authState.isAuthenticated) {
+            return { status: 'ready' };
+        }
+        return { status: 'unavailable', message: 'Not signed in to GitHub Copilot' };
+    }
+
+    async createOrUpdateLanguageModels(...modelDescriptions: CopilotModelDescription[]): Promise<void> {
+        const status = await this.calculateStatus();
+
+        for (const modelDescription of modelDescriptions) {
+            const model = await this.languageModelRegistry.getLanguageModel(modelDescription.id);
+
+            if (model) {
+                if (!(model instanceof CopilotLanguageModel)) {
+                    console.warn(`Copilot: model ${modelDescription.id} is not a Copilot model`);
+                    continue;
+                }
+                await this.languageModelRegistry.patchLanguageModel<CopilotLanguageModel>(modelDescription.id, {
+                    model: modelDescription.model,
+                    enableStreaming: modelDescription.enableStreaming,
+                    supportsStructuredOutput: modelDescription.supportsStructuredOutput,
+                    status,
+                    maxRetries: modelDescription.maxRetries
+                });
+            } else {
+                this.languageModelRegistry.addLanguageModels([
+                    new CopilotLanguageModel(
+                        modelDescription.id,
+                        modelDescription.model,
+                        status,
+                        modelDescription.enableStreaming,
+                        modelDescription.supportsStructuredOutput,
+                        modelDescription.maxRetries,
+                        () => this.authService.getAccessToken(),
+                        () => this.enterpriseUrl,
+                        this.tokenUsageService
+                    )
+                ]);
+            }
+        }
+    }
+
+    removeLanguageModels(...modelIds: string[]): void {
+        this.languageModelRegistry.removeLanguageModels(modelIds);
+    }
+
+    async refreshModelsStatus(): Promise<void> {
+        const status = await this.calculateStatus();
+        const allModels = await this.languageModelRegistry.getLanguageModels();
+
+        for (const model of allModels) {
+            if (model instanceof CopilotLanguageModel && model.id.startsWith(`${COPILOT_PROVIDER_ID}/`)) {
+                await this.languageModelRegistry.patchLanguageModel<CopilotLanguageModel>(model.id, {
+                    status
+                });
+            }
+        }
+    }
+}

packages/ai-copilot/src/node/index.ts

@@ -0,0 +1,19 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+export * from './copilot-auth-service-impl';
+export * from './copilot-language-model';
+export * from './copilot-language-models-manager-impl';

packages/ai-copilot/src/package.spec.ts

@@ -0,0 +1,27 @@
+// *****************************************************************************
+// Copyright (C) 2026 EclipseSource GmbH and others.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+/* note: this bogus test file is required so that
+   we are able to run mocha unit tests on this
+   package, without having any actual unit tests in it.
+   This way a coverage report will be generated,
+   showing 0% coverage, instead of no report.
+   This file can be removed once we have real unit
+   tests in place. */
+
+describe('ai-copilot package', () => {
+    it('support code coverage statistics', () => true);
+});

packages/ai-copilot/tsconfig.json

@@ -0,0 +1,22 @@
+{
+  "extends": "../../configs/base.tsconfig",
+  "compilerOptions": {
+    "composite": true,
+    "rootDir": "src",
+    "outDir": "lib"
+  },
+  "include": [
+    "src"
+  ],
+  "references": [
+    {
+      "path": "../ai-core"
+    },
+    {
+      "path": "../ai-openai"
+    },
+    {
+      "path": "../core"
+    }
+  ]
+}