feat: add support for custom agents

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

@@ -14,9 +14,9 @@
 // SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
 // *****************************************************************************
 
-import { Agent, AIVariableContribution } from '@theia/ai-core/lib/common';
+import { Agent, AgentService, AIVariableContribution } from '@theia/ai-core/lib/common';
 import { bindContributionProvider } from '@theia/core';
-import { PreferenceContribution } from '@theia/core/lib/browser';
+import { FrontendApplicationContribution, PreferenceContribution } from '@theia/core/lib/browser';
 import { ContainerModule } from '@theia/core/shared/inversify';
 import {
     ChatAgent,
@@ -27,13 +27,16 @@ import {
     ChatService,
     DefaultChatAgentId
 } from '../common';
+import { ChatAgentsVariableContribution } from '../common/chat-agents-variable-contribution';
 import { CommandChatAgent } from '../common/command-chat-agents';
+import { CustomChatAgent } from '../common/custom-chat-agent';
 import { OrchestratorChatAgent, OrchestratorChatAgentId } from '../common/orchestrator-chat-agent';
+import { DefaultResponseContentFactory, DefaultResponseContentMatcherProvider, ResponseContentMatcherProvider } from '../common/response-content-matcher';
 import { UniversalChatAgent } from '../common/universal-chat-agent';
 import { aiChatPreferences } from './ai-chat-preferences';
-import { ChatAgentsVariableContribution } from '../common/chat-agents-variable-contribution';
+import { AICustomAgentsFrontendApplicationContribution } from './custom-agent-frontend-application-contribution';
 import { FrontendChatServiceImpl } from './frontend-chat-service';
-import { DefaultResponseContentMatcherProvider, DefaultResponseContentFactory, ResponseContentMatcherProvider } from '../common/response-content-matcher';
+import { FactoryOfCustomAgents } from './custom-agent-factory';
 
 export default new ContainerModule(bind => {
     bindContributionProvider(bind, Agent);
@@ -69,4 +72,18 @@ export default new ContainerModule(bind => {
     bind(ChatAgent).toService(CommandChatAgent);
 
     bind(PreferenceContribution).toConstantValue({ schema: aiChatPreferences });
+
+    bind(CustomChatAgent).toSelf();
+    bind(FactoryOfCustomAgents).toFactory<CustomChatAgent, [string, string, string, string]>(
+        ctx => (id: string, name: string, description: string, prompt: string) => {
+            const agent = ctx.container.get<CustomChatAgent>(CustomChatAgent);
+            agent.id = id;
+            agent.name = name;
+            agent.description = description;
+            agent.prompt = prompt;
+            ctx.container.get<ChatAgentService>(ChatAgentService).registerChatAgent(agent);
+            ctx.container.get<AgentService>(AgentService).registerAgent(agent);
+            return agent;
+        });
+    bind(FrontendApplicationContribution).to(AICustomAgentsFrontendApplicationContribution).inSingletonScope();
 });

packages/ai-chat/src/browser/custom-agent-factory.ts

@@ -0,0 +1,20 @@
+// *****************************************************************************
+// Copyright (C) 2024 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 { CustomChatAgent } from '../common';
+
+export const FactoryOfCustomAgents = Symbol('FactoryOfCustomAgents');
+export type FactoryOfCustomAgents = (id: string, name: string, description: string, prompt: string) => CustomChatAgent;

packages/ai-chat/src/browser/custom-agent-frontend-application-contribution.ts

@@ -0,0 +1,73 @@
+// *****************************************************************************
+// Copyright (C) 2024 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 { AgentService, CustomAgentDescription, PromptCustomizationService } from '@theia/ai-core';
+import { FrontendApplicationContribution } from '@theia/core/lib/browser';
+import { inject, injectable } from '@theia/core/shared/inversify';
+import { ChatAgentService } from '../common';
+import { FactoryOfCustomAgents } from './custom-agent-factory';
+
+@injectable()
+export class AICustomAgentsFrontendApplicationContribution implements FrontendApplicationContribution {
+    @inject(FactoryOfCustomAgents)
+    protected readonly customAgentFactory: FactoryOfCustomAgents;
+
+    @inject(PromptCustomizationService)
+    protected readonly customizationService: PromptCustomizationService;
+
+    @inject(AgentService)
+    private readonly agentService: AgentService;
+
+    @inject(ChatAgentService)
+    private readonly chatAgentService: ChatAgentService;
+
+    private knownCustomAgents: Map<string, CustomAgentDescription> = new Map();
+    onStart(): void {
+        this.customizationService?.getCustomAgents().then(customAgents => {
+            customAgents.forEach(agent => {
+                this.customAgentFactory(agent.id, agent.name, agent.description, agent.prompt);
+                this.knownCustomAgents.set(agent.id, agent);
+            });
+        }).catch(e => {
+            console.error('Failed to load custom agents', e);
+        });
+        this.customizationService?.onDidChangeCustomAgents(() => {
+            this.customizationService?.getCustomAgents().then(customAgents => {
+                const customAgentsToAdd = customAgents.filter(agent =>
+                    !this.knownCustomAgents.has(agent.id) || !CustomAgentDescription.equals(this.knownCustomAgents.get(agent.id)!, agent));
+                const customAgentIdsToRemove = [...this.knownCustomAgents.values()].filter(agent =>
+                    !customAgents.find(a => CustomAgentDescription.equals(a, agent))).map(a => a.id);
+
+                // delete first so we don't have to deal with the case where we add and remove the same agentId
+                customAgentIdsToRemove.forEach(id => {
+                    this.chatAgentService.unregisterChatAgent(id);
+                    this.agentService.unregisterAgent(id);
+                    this.knownCustomAgents.delete(id);
+                });
+                customAgentsToAdd
+                    .forEach(agent => {
+                        this.customAgentFactory(agent.id, agent.name, agent.description, agent.prompt);
+                        this.knownCustomAgents.set(agent.id, agent);
+                    });
+            }).catch(e => {
+                console.error('Failed to load custom agents', e);
+            });
+        });
+    }
+
+    onStop(): void {
+    }
+}

packages/ai-chat/src/common/chat-agent-service.ts

@@ -41,6 +41,18 @@ export interface ChatAgentService {
      * Returns all agents, including disabled ones.
      */
     getAllAgents(): ChatAgent[];
+
+    /**
+     * Allows to register a chat agent programmatically.
+     * @param agent the agent to register
+     */
+    registerChatAgent(agent: ChatAgent): void;
+
+    /**
+     * Allows to unregister a chat agent programmatically.
+     * @param agentId the agent id to unregister
+     */
+    unregisterChatAgent(agentId: string): void;
 }
 @injectable()
 export class ChatAgentServiceImpl implements ChatAgentService {
@@ -65,6 +77,9 @@ export class ChatAgentServiceImpl implements ChatAgentService {
     registerChatAgent(agent: ChatAgent): void {
         this._agents.push(agent);
     }
+    unregisterChatAgent(agentId: string): void {
+        this._agents = this._agents.filter(a => a.id !== agentId);
+    }
 
     getAgent(id: string): ChatAgent | undefined {
         if (!this._agentIsEnabled(id)) {

packages/ai-chat/src/common/custom-chat-agent.ts

@@ -0,0 +1,44 @@
+// *****************************************************************************
+// Copyright (C) 2024 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 { AgentSpecificVariables, PromptTemplate } from '@theia/ai-core';
+import { AbstractStreamParsingChatAgent, ChatAgent, SystemMessageDescription } from './chat-agents';
+import { injectable } from '@theia/core/shared/inversify';
+
+@injectable()
+export class CustomChatAgent
+    extends AbstractStreamParsingChatAgent
+    implements ChatAgent {
+    name: string;
+    description: string;
+    readonly variables: string[] = [];
+    readonly functions: string[] = [];
+    readonly promptTemplates: PromptTemplate[] = [];
+    readonly agentSpecificVariables: AgentSpecificVariables[] = [];
+
+    constructor(
+    ) {
+        super('CustomChatAgent', [{ purpose: 'chat' }], 'chat');
+    }
+    protected override async getSystemMessageDescription(): Promise<SystemMessageDescription | undefined> {
+        const resolvedPrompt = await this.promptService.getPrompt(`${this.name}_prompt`);
+        return resolvedPrompt ? SystemMessageDescription.fromResolvedPromptTemplate(resolvedPrompt) : undefined;
+    }
+
+    set prompt(prompt: string) {
+        this.promptTemplates.push({ id: `${this.name}_system`, template: prompt });
+    }
+}

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

@@ -13,12 +13,13 @@
 //
 // SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
 // *****************************************************************************
-export * from './chat-agent-service';
 export * from './chat-agents';
+export * from './chat-agent-service';
 export * from './chat-model';
-export * from './parsed-chat-request';
 export * from './chat-request-parser';
 export * from './chat-service';
 export * from './command-chat-agents';
-export * from './universal-chat-agent';
+export * from './custom-chat-agent';
+export * from './parsed-chat-request';
 export * from './orchestrator-chat-agent';
+export * from './universal-chat-agent';

packages/ai-core/package.json

@@ -11,6 +11,8 @@
     "@theia/output": "1.54.0",
     "@theia/variable-resolver": "1.54.0",
     "@theia/workspace": "1.54.0",
+    "@types/js-yaml": "^4.0.9",
+    "js-yaml": "^4.1.0",
     "minimatch": "^5.1.0",
     "tslib": "^2.6.2"
   },

packages/ai-core/src/browser/ai-configuration/agent-configuration-widget.tsx

@@ -87,6 +87,7 @@ export class AIAgentConfigurationWidget extends ReactWidget {
 
         this.aiSettingsService.onDidChange(() => this.update());
         this.aiConfigurationSelectionService.onDidAgentChange(() => this.update());
+        this.agentService.onDidChangeAgents(() => this.update());
         this.update();
     }
 
@@ -100,6 +101,7 @@ export class AIAgentConfigurationWidget extends ReactWidget {
                         </li>
                     )}
                 </ul>
+                <button style={{ marginLeft: 0 }} className='theia-button main' onClick={() => this.addCustomAgent()}>Add Custom Agent</button>
             </div>
             <div className='configuration-agent-panel preferences-editor-widget'>
                 {this.renderAgentDetails()}
@@ -205,6 +207,10 @@ export class AIAgentConfigurationWidget extends ReactWidget {
         this.aiConfigurationSelectionService.selectConfigurationTab(AIVariableConfigurationWidget.ID);
     }
 
+    protected addCustomAgent(): void {
+        this.promptCustomizationService.openCustomAgentYaml();
+    }
+
     protected setActiveAgent(agent: Agent): void {
         this.aiConfigurationSelectionService.setActiveAgent(agent);
         this.update();

packages/ai-core/src/browser/frontend-prompt-customization-service.ts

@@ -17,13 +17,14 @@
 import { DisposableCollection, URI, Event, Emitter } from '@theia/core';
 import { OpenerService } from '@theia/core/lib/browser';
 import { inject, injectable, postConstruct } from '@theia/core/shared/inversify';
-import { PromptCustomizationService, PromptTemplate } from '../common';
+import { PromptCustomizationService, PromptTemplate, CustomAgentDescription } from '../common';
 import { BinaryBuffer } from '@theia/core/lib/common/buffer';
 import { FileService } from '@theia/filesystem/lib/browser/file-service';
 import { FileChangesEvent } from '@theia/filesystem/lib/common/files';
 import { AICorePreferences, PREFERENCE_NAME_PROMPT_TEMPLATES } from './ai-core-preferences';
 import { AgentService } from '../common/agent-service';
 import { EnvVariablesServer } from '@theia/core/lib/common/env-variables';
+import { load } from 'js-yaml';
 
 @injectable()
 export class FrontendPromptCustomizationServiceImpl implements PromptCustomizationService {
@@ -51,6 +52,9 @@ export class FrontendPromptCustomizationServiceImpl implements PromptCustomizati
     private readonly onDidChangePromptEmitter = new Emitter<string>();
     readonly onDidChangePrompt: Event<string> = this.onDidChangePromptEmitter.event;
 
+    private readonly onDidChangeCustomAgentsEmitter = new Emitter<void>();
+    readonly onDidChangeCustomAgents = this.onDidChangeCustomAgentsEmitter.event;
+
     @postConstruct()
     protected init(): void {
         this.preferences.onPreferenceChanged(event => {
@@ -72,6 +76,9 @@ export class FrontendPromptCustomizationServiceImpl implements PromptCustomizati
 
         this.toDispose.push(this.fileService.watch(templateURI, { recursive: true, excludes: [] }));
         this.toDispose.push(this.fileService.onDidFilesChange(async (event: FileChangesEvent) => {
+            if (event.changes.some(change => change.resource.toString().endsWith('customAgents.yml'))) {
+                this.onDidChangeCustomAgentsEmitter.fire();
+            }
             // check deleted templates
             for (const deletedFile of event.getDeleted()) {
                 if (this.trackedTemplateURIs.has(deletedFile.resource.toString())) {
@@ -194,4 +201,32 @@ export class FrontendPromptCustomizationServiceImpl implements PromptCustomizati
         return undefined;
     }
 
+    async getCustomAgents(): Promise<CustomAgentDescription[]> {
+        const customAgentYamlUri = (await this.getTemplatesDirectoryURI()).resolve('customAgents.yml');
+        const yamlExists = await this.fileService.exists(customAgentYamlUri);
+        if (!yamlExists) {
+            return [];
+        }
+        const filecontent = await this.fileService.read(customAgentYamlUri, { encoding: 'utf-8' });
+        try {
+            const doc = load(filecontent.value);
+            if (!Array.isArray(doc) || !doc.every(entry => CustomAgentDescription.is(entry))) {
+                console.debug('Invalid customAgents.yml file content');
+                return [];
+            }
+            return doc as CustomAgentDescription[];
+        } catch (e) {
+            console.debug(e.message, e);
+            return [];
+        }
+    }
+
+    async openCustomAgentYaml(): Promise<void> {
+        const customAgentYamlUri = (await this.getTemplatesDirectoryURI()).resolve('customAgents.yml');
+        if (! await this.fileService.exists(customAgentYamlUri)) {
+            await this.fileService.createFile(customAgentYamlUri);
+        }
+        const openHandler = await this.openerService.getOpener(customAgentYamlUri);
+        openHandler.open(customAgentYamlUri);
+    }
 }

packages/ai-core/src/common/agent-service.ts

@@ -14,7 +14,7 @@
 // SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
 // *****************************************************************************
 import { inject, injectable, named, optional, postConstruct } from '@theia/core/shared/inversify';
-import { ContributionProvider } from '@theia/core';
+import { ContributionProvider, Emitter, Event } from '@theia/core';
 import { Agent } from './agent';
 import { AISettingsService } from './settings-service';
 
@@ -48,6 +48,24 @@ export interface AgentService {
      * @return true if the agent is enabled, false otherwise.
      */
     isEnabled(agentId: string): boolean;
+
+    /**
+     * Allows to register an agent programmatically.
+     * @param agent the agent to register
+     */
+    registerAgent(agent: Agent): void;
+
+    /**
+     * Allows to unregister an agent programmatically.
+     * @param agentId the agent id to unregister
+     */
+    unregisterAgent(agentId: string): void;
+
+    /**
+     * Emitted when the list of agents changes.
+     * This can be used to update the UI when agents are added or removed.
+     */
+    onDidChangeAgents: Event<void>;
 }
 
 @injectable()
@@ -63,6 +81,9 @@ export class AgentServiceImpl implements AgentService {
 
     protected _agents: Agent[] = [];
 
+    private readonly onDidChangeAgentsEmitter = new Emitter<void>();
+    readonly onDidChangeAgents = this.onDidChangeAgentsEmitter.event;
+
     @postConstruct()
     protected init(): void {
         this.aiSettingsService?.getSettings().then(settings => {
@@ -82,6 +103,12 @@ export class AgentServiceImpl implements AgentService {
 
     registerAgent(agent: Agent): void {
         this._agents.push(agent);
+        this.onDidChangeAgentsEmitter.fire();
+    }
+
+    unregisterAgent(agentId: string): void {
+        this._agents = this._agents.filter(a => a.id !== agentId);
+        this.onDidChangeAgentsEmitter.fire();
     }
 
     getAgents(): Agent[] {