feat: CodeBuddy Code ACP integration

src/agent/AgentBackend.ts

@@ -48,7 +48,7 @@ export interface McpServerConfig {
 export type AgentTransport = 'native-claude' | 'mcp-codex' | 'acp';
 
 /** Agent identifier */
-export type AgentId = 'claude' | 'codex' | 'gemini' | 'opencode' | 'claude-acp' | 'codex-acp';
+export type AgentId = 'claude' | 'codex' | 'gemini' | 'opencode' | 'claude-acp' | 'codex-acp' | 'codebuddy' | 'codebuddy-acp';
 
 /**
  * Configuration for creating an agent backend

src/agent/acp/codebuddy.ts

@@ -0,0 +1,130 @@
+/**
+ * CodeBuddy ACP Backend - CodeBuddy Code agent via ACP
+ * 
+ * This module provides a factory function for creating a CodeBuddy backend
+ * that communicates using the Agent Client Protocol (ACP).
+ * 
+ * CodeBuddy Code supports ACP for external tool integration and communication.
+ */
+
+import { AcpSdkBackend, type AcpSdkBackendOptions, type AcpPermissionHandler } from './AcpSdkBackend';
+import type { AgentBackend, McpServerConfig } from '../AgentBackend';
+import { agentRegistry, type AgentFactoryOptions } from '../AgentRegistry';
+import { logger } from '@/ui/logger';
+import { 
+  CODEBUDDY_API_KEY_ENV, 
+  CODEBUDDY_MODEL_ENV, 
+  DEFAULT_CODEBUDDY_MODEL,
+  CODEBUDDY_CLI_COMMAND
+} from '@/codebuddy/constants';
+import { 
+  readCodebuddyLocalConfig, 
+  determineCodebuddyModel,
+  getCodebuddyModelSource
+} from '@/codebuddy/utils/config';
+
+/**
+ * Options for creating a CodeBuddy ACP backend
+ */
+export interface CodebuddyBackendOptions extends AgentFactoryOptions {
+  /** API key for CodeBuddy (defaults to CODEBUDDY_API_KEY env var) */
+  apiKey?: string;
+
+  /** OAuth token from Happy cloud - highest priority */
+  cloudToken?: string;
+
+  /** Model to use. If undefined, will use local config, env var, or default.
+   *  If explicitly set to null, will use default (skip local config).
+   *  (defaults to CODEBUDDY_MODEL env var or 'claude-sonnet-4-20250514') */
+  model?: string | null;
+
+  /** MCP servers to make available to the agent */
+  mcpServers?: Record<string, McpServerConfig>;
+
+  /** Optional permission handler for tool approval */
+  permissionHandler?: AcpPermissionHandler;
+}
+
+/**
+ * Create a CodeBuddy backend using ACP (official SDK).
+ * 
+ * The CodeBuddy CLI must be installed and available in PATH.
+ * Uses ACP mode for communication.
+ * 
+ * @param options - Configuration options
+ * @returns AgentBackend instance for CodeBuddy
+ */
+export function createCodebuddyBackend(options: CodebuddyBackendOptions): AgentBackend {
+
+  // Resolve API key from multiple sources (in priority order):
+  // 1. Happy cloud OAuth token
+  // 2. Local CodeBuddy config files (~/.codebuddy/)
+  // 3. CODEBUDDY_API_KEY environment variable
+  // 4. Explicit apiKey option
+
+  // Try reading from local CodeBuddy config (token and model)
+  const localConfig = readCodebuddyLocalConfig();
+
+  let apiKey = options.cloudToken       // 1. Happy cloud token (passed from runCodebuddy)
+    || localConfig.token                // 2. Local config (~/.codebuddy/)
+    || process.env[CODEBUDDY_API_KEY_ENV]  // 3. CODEBUDDY_API_KEY env var
+    || options.apiKey;                  // 4. Explicit apiKey option (fallback)
+
+  if (!apiKey) {
+    logger.warn(`[CodeBuddy] No API key found. Set ${CODEBUDDY_API_KEY_ENV} environment variable or configure authentication.`);
+  }
+
+  // Command to run codebuddy
+  const codebuddyCommand = CODEBUDDY_CLI_COMMAND;
+
+  // Get model from options, local config, system environment, or use default
+  const model = determineCodebuddyModel(options.model, localConfig);
+
+  // Build args - use ACP mode flag
+  // Note: The actual flag might need to be adjusted based on CodeBuddy CLI implementation
+  const codebuddyArgs = ['--acp'];
+
+  const backendOptions: AcpSdkBackendOptions = {
+    agentName: 'codebuddy',
+    cwd: options.cwd,
+    command: codebuddyCommand,
+    args: codebuddyArgs,
+    env: {
+      ...options.env,
+      ...(apiKey ? { [CODEBUDDY_API_KEY_ENV]: apiKey } : {}),
+      // Pass model via env var
+      [CODEBUDDY_MODEL_ENV]: model,
+      // Suppress debug output to avoid stdout pollution
+      NODE_ENV: 'production',
+      DEBUG: '',
+    },
+    mcpServers: options.mcpServers,
+    permissionHandler: options.permissionHandler,
+  };
+
+  // Determine model source for logging
+  const modelSource = getCodebuddyModelSource(options.model, localConfig);
+
+  logger.debug('[CodeBuddy] Creating ACP SDK backend with options:', {
+    cwd: backendOptions.cwd,
+    command: backendOptions.command,
+    args: backendOptions.args,
+    hasApiKey: !!apiKey,
+    model: model,
+    modelSource: modelSource,
+    mcpServerCount: options.mcpServers ? Object.keys(options.mcpServers).length : 0,
+  });
+
+  return new AcpSdkBackend(backendOptions);
+}
+
+/**
+ * Register CodeBuddy backend with the global agent registry.
+ * 
+ * This function should be called during application initialization
+ * to make the CodeBuddy agent available for use.
+ */
+export function registerCodebuddyAgent(): void {
+  agentRegistry.register('codebuddy', (opts) => createCodebuddyBackend(opts));
+  logger.debug('[CodeBuddy] Registered with agent registry');
+}

src/agent/acp/index.ts

@@ -9,4 +9,5 @@
 
 export { AcpSdkBackend, type AcpSdkBackendOptions } from './AcpSdkBackend';
 export { createGeminiBackend, registerGeminiAgent, type GeminiBackendOptions } from './gemini';
+export { createCodebuddyBackend, registerCodebuddyAgent, type CodebuddyBackendOptions } from './codebuddy';
 

src/api/api.ts

@@ -320,7 +320,7 @@ export class ApiClient {
    * Get vendor API token from the server
    * Returns the token if it exists, null otherwise
    */
-  async getVendorToken(vendor: 'openai' | 'anthropic' | 'gemini'): Promise<any | null> {
+  async getVendorToken(vendor: 'openai' | 'anthropic' | 'gemini' | 'codebuddy'): Promise<any | null> {
     try {
       const response = await axios.get(
         `${configuration.serverUrl}/v1/connect/${vendor}/token`,

src/codebuddy/constants.ts

@@ -0,0 +1,67 @@
+/**
+ * CodeBuddy Constants
+ * 
+ * Centralized constants for CodeBuddy Code integration including environment variable names,
+ * default values, and directory/file path patterns.
+ */
+
+import { trimIdent } from '@/utils/trimIdent';
+
+/** Environment variable name for CodeBuddy API key */
+export const CODEBUDDY_API_KEY_ENV = 'CODEBUDDY_API_KEY';
+
+/** Environment variable name for CodeBuddy model selection */
+export const CODEBUDDY_MODEL_ENV = 'CODEBUDDY_MODEL';
+
+/** Default CodeBuddy model */
+export const DEFAULT_CODEBUDDY_MODEL = 'claude-sonnet-4-20250514';
+
+/** CodeBuddy CLI command */
+export const CODEBUDDY_CLI_COMMAND = 'codebuddy';
+
+/**
+ * Directory names for CodeBuddy configuration
+ * Based on CodeBuddy Code documentation
+ */
+export const CODEBUDDY_DIR = '.codebuddy';
+
+/** User-level CodeBuddy directory */
+export const CODEBUDDY_USER_DIR = '~/.codebuddy';
+
+/** Memory file name */
+export const CODEBUDDY_MEMORY_FILE = 'CODEBUDDY.md';
+
+/** Local memory file name (not committed to git) */
+export const CODEBUDDY_LOCAL_MEMORY_FILE = 'CODEBUDDY.local.md';
+
+/** Settings file name */
+export const CODEBUDDY_SETTINGS_FILE = 'settings.json';
+
+/** Local settings file name */
+export const CODEBUDDY_LOCAL_SETTINGS_FILE = 'settings.local.json';
+
+/** Rules directory name */
+export const CODEBUDDY_RULES_DIR = 'rules';
+
+/** Agents directory name */
+export const CODEBUDDY_AGENTS_DIR = 'agents';
+
+/**
+ * Instruction for changing chat title
+ * Used in system prompts to instruct agents to call change_title function
+ */
+export const CHANGE_TITLE_INSTRUCTION = trimIdent(
+  `Based on this message, call functions.happy__change_title to change chat session title that would represent the current task. If chat idea would change dramatically - call this function again to update the title.`
+);
+
+/**
+ * Available CodeBuddy models
+ */
+export const AVAILABLE_CODEBUDDY_MODELS = [
+  'claude-sonnet-4-20250514',
+  'claude-opus-4-20250514', 
+  'claude-3-5-sonnet-20241022',
+  'claude-3-5-haiku-20241022',
+] as const;
+
+export type CodebuddyModel = typeof AVAILABLE_CODEBUDDY_MODELS[number];

src/codebuddy/index.ts

@@ -0,0 +1,77 @@
+/**
+ * CodeBuddy Module
+ * 
+ * Main entry point for CodeBuddy Code integration.
+ * Exports all public types, constants, and utilities.
+ */
+
+// Types
+export type { 
+  CodebuddyMode, 
+  CodexMessagePayload,
+  CodebuddyLocalConfig,
+  CodebuddySettings,
+  CodebuddyMemory,
+  CodebuddyRule
+} from './types';
+
+// Constants
+export {
+  CODEBUDDY_API_KEY_ENV,
+  CODEBUDDY_MODEL_ENV,
+  DEFAULT_CODEBUDDY_MODEL,
+  CODEBUDDY_CLI_COMMAND,
+  CODEBUDDY_DIR,
+  CODEBUDDY_USER_DIR,
+  CODEBUDDY_MEMORY_FILE,
+  CODEBUDDY_LOCAL_MEMORY_FILE,
+  CODEBUDDY_SETTINGS_FILE,
+  CODEBUDDY_LOCAL_SETTINGS_FILE,
+  CODEBUDDY_RULES_DIR,
+  CODEBUDDY_AGENTS_DIR,
+  CHANGE_TITLE_INSTRUCTION,
+  AVAILABLE_CODEBUDDY_MODELS,
+  type CodebuddyModel
+} from './constants';
+
+// Configuration utilities
+export {
+  getUserCodebuddyDir,
+  getProjectCodebuddyDir,
+  readCodebuddyLocalConfig,
+  readCodebuddySettings,
+  readCodebuddyMemory,
+  readCodebuddyRules,
+  determineCodebuddyModel,
+  saveCodebuddyModelToConfig,
+  getInitialCodebuddyModel,
+  getCodebuddyModelSource,
+  buildSystemPrompt
+} from './utils/config';
+
+// Permission handler
+export { CodebuddyPermissionHandler } from './utils/permissionHandler';
+export type { PermissionResult, PendingRequest } from './utils/permissionHandler';
+
+// Reasoning processor
+export { CodebuddyReasoningProcessor } from './utils/reasoningProcessor';
+export type { 
+  ReasoningToolCall, 
+  ReasoningToolResult, 
+  ReasoningMessage, 
+  ReasoningOutput 
+} from './utils/reasoningProcessor';
+
+// Diff processor
+export { CodebuddyDiffProcessor } from './utils/diffProcessor';
+export type { DiffToolCall, DiffToolResult } from './utils/diffProcessor';
+
+// Options parser
+export {
+  hasIncompleteOptions,
+  parseOptionsFromText,
+  formatOptionsXml
+} from './utils/optionsParser';
+
+// Main entry point
+export { runCodebuddy } from './runCodebuddy';