feat: add LiteLLM as AI gateway provider

src/config/index.ts

@@ -23,6 +23,7 @@ export interface TempestSettings {
     anthropic?: string;
     openai?: string;
     xai?: string;
+    litellm?: string;
   };
 
   // Default LLM settings
@@ -61,6 +62,12 @@ export interface TempestSettings {
     defaultModel: string;
   };
 
+  // LiteLLM AI gateway proxy — routes to 100+ LLM providers via unified API
+  litellm: {
+    baseUrl: string;
+    defaultModel: string;
+  };
+
   // Codex CLI/account subscription backend
   codex: {
     command: string;
@@ -124,6 +131,11 @@ const DEFAULT_SETTINGS: TempestSettings = {
     defaultModel: 'grok-build-0.1',
   },
 
+  litellm: {
+    baseUrl: 'http://localhost:4000/v1',
+    defaultModel: 'gpt-4o',
+  },
+
   codex: {
     command: 'codex',
     defaultModel: 'codex-default',
@@ -381,6 +393,16 @@ export const AVAILABLE_MODELS: Record<LLMProvider, ModelInfo[]> = {
       capabilities: ['reasoning', 'code', 'analysis', 'vision', 'fast'],
     },
   ],
+  litellm: [
+    {
+      id: 'gpt-4o',
+      name: 'Any model via LiteLLM proxy (default: gpt-4o)',
+      provider: 'LiteLLM',
+      contextWindow: 128000,
+      maxOutput: 4096,
+      capabilities: ['reasoning', 'code', 'analysis', 'vision', 'tools'],
+    },
+  ],
   codex: [
     {
       id: 'codex-default',
@@ -547,7 +569,7 @@ class ConfigManager {
   /**
    * Set an API key for a provider
    */
-  setApiKey(provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai', key: string): void {
+  setApiKey(provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai' | 'litellm', key: string): void {
     const apiKeys = this.config.get('apiKeys');
     apiKeys[provider] = key;
     this.config.set('apiKeys', apiKeys);
@@ -556,7 +578,7 @@ class ConfigManager {
   /**
    * Get an API key for a provider
    */
-  getApiKey(provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai'): string | undefined {
+  getApiKey(provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai' | 'litellm'): string | undefined {
     // First check environment variables (highest priority)
     const envVarMap = {
       openrouter: 'OPENROUTER_API_KEY',
@@ -564,6 +586,7 @@ class ConfigManager {
       anthropic: 'ANTHROPIC_API_KEY',
       openai: 'OPENAI_API_KEY',
       xai: 'XAI_API_KEY',
+      litellm: 'LITELLM_API_KEY',
     };
 
     // Force a fully UNCONFIGURED server (no key from env OR the saved store) — used by
@@ -582,7 +605,7 @@ class ConfigManager {
   /**
    * Check if a provider has a valid API key configured
    */
-  hasApiKey(provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai'): boolean {
+  hasApiKey(provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai' | 'litellm'): boolean {
     const key = this.getApiKey(provider);
     return !!key && key.length > 10;
   }
@@ -590,12 +613,22 @@ class ConfigManager {
   /**
    * Remove an API key
    */
-  removeApiKey(provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai'): void {
+  removeApiKey(provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai' | 'litellm'): void {
     const apiKeys = this.config.get('apiKeys');
     delete apiKeys[provider];
     this.config.set('apiKeys', apiKeys);
   }
 
+  /**
+   * Check if a LiteLLM proxy is configured (base URL set via env or config)
+   */
+  hasLiteLLMProxy(): boolean {
+    const envUrl = process.env.LITELLM_BASE_URL?.trim();
+    if (envUrl) return true;
+    const storedUrl = this.config.get('litellm')?.baseUrl;
+    return !!storedUrl && storedUrl !== 'http://localhost:4000/v1';
+  }
+
   /**
    * Get configured providers (those with API keys)
    */
@@ -607,6 +640,7 @@ class ConfigManager {
     if (this.hasApiKey('anthropic')) providers.push('anthropic');
     if (this.hasApiKey('openai')) providers.push('openai');
     if (this.hasApiKey('xai')) providers.push('xai');
+    if (this.hasLiteLLMProxy()) providers.push('litellm');
 
     // Codex uses the local Codex CLI/account auth instead of API-key storage.
     providers.push('codex');
@@ -654,6 +688,11 @@ class ConfigManager {
         baseUrl = this.config.get('xai').baseUrl;
         actualModel = model || this.config.get('xai').defaultModel;
         break;
+      case 'litellm':
+        apiKey = this.getApiKey('litellm');
+        baseUrl = process.env.LITELLM_BASE_URL?.trim() || this.config.get('litellm').baseUrl;
+        actualModel = model || process.env.LITELLM_MODEL?.trim() || this.config.get('litellm').defaultModel;
+        break;
       case 'codex':
         actualModel = model || this.config.get('codex').defaultModel;
         break;
@@ -699,8 +738,9 @@ class ConfigManager {
     const flag = (process.env.TEMPEST_MODEL_FALLBACK || '').trim().toLowerCase();
     if (!flag || ['0', 'false', 'off', 'no'].includes(flag)) return [];
     const chain: FallbackEntry[] = [];
-    const add = (p: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai') => {
+    const add = (p: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai' | 'litellm') => {
-      if (p === primary || !this.hasApiKey(p)) return;
+      if (p === primary) return;
+      if (p === 'litellm' ? !this.hasLiteLLMProxy() : !this.hasApiKey(p)) return;
       chain.push({
         provider: p,
         model: this.config.get(p).defaultModel,
@@ -710,6 +750,7 @@ class ConfigManager {
     };
     add('openrouter');
     add('venice');
+    add('litellm');
     add('anthropic');
     add('openai');
     add('xai');
@@ -736,6 +777,9 @@ class ConfigManager {
       case 'openai':
         this.config.set('defaultModel', this.config.get('openai').defaultModel);
         break;
+      case 'litellm':
+        this.config.set('defaultModel', this.config.get('litellm').defaultModel);
+        break;
       case 'codex':
         this.config.set('defaultModel', this.config.get('codex').defaultModel);
         break;
@@ -759,6 +803,9 @@ class ConfigManager {
       case 'openai':
         this.config.set('openai', { ...this.config.get('openai'), defaultModel: model });
         break;
+      case 'litellm':
+        this.config.set('litellm', { ...this.config.get('litellm'), defaultModel: model });
+        break;
       case 'codex':
         this.config.set('codex', { ...this.config.get('codex'), defaultModel: model });
         break;
@@ -797,6 +844,7 @@ class ConfigManager {
         anthropic: settings.apiKeys.anthropic ? '***REDACTED***' : undefined,
         openai: settings.apiKeys.openai ? '***REDACTED***' : undefined,
         xai: settings.apiKeys.xai ? '***REDACTED***' : undefined,
+        litellm: settings.apiKeys.litellm ? '***REDACTED***' : undefined,
       },
     };
     writeFileSync(filePath, JSON.stringify(safeSettings, null, 2));
@@ -829,6 +877,12 @@ OPENAI_API_KEY=
 # xAI API Key
 # Get your key at: https://console.x.ai/
 XAI_API_KEY=
+
+# LiteLLM Proxy (AI gateway — 100+ providers via single API)
+# Docs: https://docs.litellm.ai/docs/proxy/quick_start
+LITELLM_BASE_URL=http://localhost:4000/v1
+LITELLM_API_KEY=
+LITELLM_MODEL=gpt-4o
 `;
     writeFileSync(filePath, template);
   }
@@ -841,8 +895,8 @@ XAI_API_KEY=
 export const config = new ConfigManager();
 
 // Helper functions for quick access
-export const getApiKey = (provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai') => config.getApiKey(provider);
+export const getApiKey = (provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai' | 'litellm') => config.getApiKey(provider);
-export const setApiKey = (provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai', key: string) => config.setApiKey(provider, key);
+export const setApiKey = (provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai' | 'litellm', key: string) => config.setApiKey(provider, key);
-export const hasApiKey = (provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai') => config.hasApiKey(provider);
+export const hasApiKey = (provider: 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai' | 'litellm') => config.hasApiKey(provider);
 export const getLLMConfig = (provider?: LLMProvider, model?: string) => config.getLLMConfig(provider, model);
 export const getConfiguredProviders = () => config.getConfiguredProviders();

src/index.ts

@@ -44,6 +44,7 @@ export {
   createAnthropicBackbone,
   createOpenRouterBackbone,
   createOpenAIBackbone,
+  createLiteLLMBackbone,
   createMockBackbone,
   createLocalBackbone,
   createBestAvailableBackbone,

src/llm/index.ts

@@ -4,6 +4,7 @@
  * Multi-provider LLM integration supporting:
  * - OpenRouter (recommended - access to Claude, GPT-4, Llama, etc.)
  * - Venice (OpenAI-compatible, privacy-focused / uncensored models)
+ * - LiteLLM (OpenAI-compatible AI gateway — 100+ providers via unified proxy)
  * - Anthropic (direct Claude access)
  * - OpenAI (GPT models)
  * - Mock (for testing)
@@ -360,6 +361,28 @@ class VeniceAdapter extends OpenRouterAdapter {
   }
 }
 
+// =============================================================================
+// LITELLM ADAPTER
+// =============================================================================
+// LiteLLM is an AI gateway proxy that routes to 100+ LLM providers through a
+// single OpenAI-compatible API. Same wire shape as OpenRouter (Bearer auth,
+// POST /chat/completions, identical request/response + tool-calling + SSE
+// stream), so it reuses the entire OpenRouter adapter and only differs in its
+// default base URL and the key-required error message.
+class LiteLLMAdapter extends OpenRouterAdapter {
+  name = 'litellm';
+
+  validateConfig(): { valid: boolean; error?: string } {
+    if (!this.config.baseUrl) {
+      return {
+        valid: false,
+        error: 'LiteLLM proxy base URL is required. Set LITELLM_BASE_URL or configure via tempest setup. Docs: https://docs.litellm.ai/docs/proxy/quick_start',
+      };
+    }
+    return { valid: true };
+  }
+}
+
 // =============================================================================
 // ANTHROPIC ADAPTER
 // =============================================================================
@@ -1197,6 +1220,8 @@ export class LLMBackbone extends EventEmitter<LLMEvents> {
         return new OpenRouterAdapter(config);
       case 'venice':
         return new VeniceAdapter(config);
+      case 'litellm':
+        return new LiteLLMAdapter(config);
       case 'anthropic':
         return new AnthropicAdapter(config);
       case 'openai':
@@ -1477,6 +1502,13 @@ export function createOpenAIBackbone(apiKey?: string, model?: string): LLMBackbo
   return new LLMBackbone(llmConfig);
 }
 
+export function createLiteLLMBackbone(apiKey?: string, model?: string, baseUrl?: string): LLMBackbone {
+  const llmConfig = config.getLLMConfig('litellm', model);
+  if (apiKey) llmConfig.apiKey = apiKey;
+  if (baseUrl) llmConfig.baseUrl = baseUrl;
+  return new LLMBackbone(llmConfig);
+}
+
 export function createMockBackbone(): LLMBackbone {
   return new LLMBackbone({
     provider: 'mock',
@@ -1500,7 +1532,7 @@ export function createLocalBackbone(model?: string, baseUrl?: string): LLMBackbo
  * Create the best available backbone based on configured API keys
  */
 export function createBestAvailableBackbone(): LLMBackbone {
-  // Priority: OpenRouter > Venice > Anthropic > OpenAI > Local > Mock
+  // Priority: OpenRouter > Venice > LiteLLM > Anthropic > OpenAI > Local > Mock
   const providers = config.getConfiguredProviders();
 
   if (providers.includes('openrouter')) {
@@ -1509,6 +1541,9 @@ export function createBestAvailableBackbone(): LLMBackbone {
   if (providers.includes('venice')) {
     return createVeniceBackbone();
   }
+  if (providers.includes('litellm')) {
+    return createLiteLLMBackbone();
+  }
   if (providers.includes('anthropic')) {
     return createAnthropicBackbone();
   }

src/setup.ts

@@ -240,6 +240,88 @@ async function setupOpenAIKey(): Promise<boolean> {
   }
 }
 
+async function setupLiteLLMProxy(): Promise<boolean> {
+  console.log('');
+  showInfo('LiteLLM is an AI gateway proxy that routes to 100+ LLM providers.');
+  showInfo('Docs: ' + chalk.underline('https://docs.litellm.ai/docs/proxy/quick_start'));
+  console.log('');
+
+  const { baseUrl } = await inquirer.prompt([
+    {
+      type: 'input',
+      name: 'baseUrl',
+      message: 'Enter your LiteLLM proxy base URL:',
+      default: 'http://localhost:4000/v1',
+      validate: (input: string) => {
+        if (!input || !input.startsWith('http')) {
+          return 'Please enter a valid URL (e.g. http://localhost:4000/v1)';
+        }
+        return true;
+      },
+    },
+  ]);
+
+  const { apiKey } = await inquirer.prompt([
+    {
+      type: 'password',
+      name: 'apiKey',
+      message: 'Enter your LiteLLM API key (leave blank if not required):',
+      mask: '*',
+    },
+  ]);
+
+  const { model } = await inquirer.prompt([
+    {
+      type: 'input',
+      name: 'model',
+      message: 'Enter the default model (uses LiteLLM model format, e.g. gpt-4o, anthropic/claude-sonnet-4-6):',
+      default: 'gpt-4o',
+    },
+  ]);
+
+  const spinner = ora('Testing LiteLLM proxy connection...').start();
+
+  try {
+    const llm = new LLMBackbone({
+      provider: 'litellm',
+      model,
+      apiKey: apiKey || undefined,
+      baseUrl,
+      maxTokens: 10,
+      temperature: 0,
+    });
+
+    await llm.prompt('Hello', undefined, { maxTokens: 10 });
+    spinner.succeed('LiteLLM proxy connection successful!');
+
+    config.set('litellm', { baseUrl, defaultModel: model });
+    if (apiKey) setApiKey('litellm', apiKey);
+    showSuccess('LiteLLM proxy configured successfully!');
+
+    return true;
+  } catch (error) {
+    spinner.fail('LiteLLM proxy connection failed');
+    showError(`Error: ${error instanceof Error ? error.message : String(error)}`);
+
+    const { saveAnyway } = await inquirer.prompt([
+      {
+        type: 'confirm',
+        name: 'saveAnyway',
+        message: 'Save the configuration anyway? (proxy may not be running yet)',
+        default: true,
+      },
+    ]);
+
+    if (saveAnyway) {
+      config.set('litellm', { baseUrl, defaultModel: model });
+      if (apiKey) setApiKey('litellm', apiKey);
+      showSuccess('LiteLLM proxy configuration saved.');
+      return true;
+    }
+    return false;
+  }
+}
+
 // =============================================================================
 // MODEL SELECTION
 // =============================================================================
@@ -285,6 +367,7 @@ You'll need an API key from one of these providers:
 • ${chalk.cyan('OpenRouter')} (recommended) - Access multiple models
 • ${chalk.cyan('Anthropic')} - Direct Claude access
 • ${chalk.cyan('OpenAI')} - GPT models
+• ${chalk.cyan('LiteLLM')} - AI gateway proxy (100+ providers)
 
 The setup will guide you through:
 1. Adding your API key(s)
@@ -384,6 +467,10 @@ async function setupApiKeys(): Promise<void> {
           name: `OpenAI ${hasApiKey('openai') ? chalk.green('(configured)') : ''}`,
           value: 'openai',
         },
+        {
+          name: `LiteLLM Proxy ${config.hasLiteLLMProxy() ? chalk.green('(configured)') : chalk.gray('(100+ providers via gateway)')}`,
+          value: 'litellm',
+        },
       ],
     },
   ]);
@@ -402,6 +489,9 @@ async function setupApiKeys(): Promise<void> {
       case 'openai':
         await setupOpenAIKey();
         break;
+      case 'litellm':
+        await setupLiteLLMProxy();
+        break;
     }
   }
 }
@@ -413,6 +503,7 @@ async function setupProvider(): Promise<void> {
   if (hasApiKey('venice')) configuredProviders.push({ name: 'Venice', value: 'venice' });
   if (hasApiKey('anthropic')) configuredProviders.push({ name: 'Anthropic', value: 'anthropic' });
   if (hasApiKey('openai')) configuredProviders.push({ name: 'OpenAI', value: 'openai' });
+  if (config.hasLiteLLMProxy()) configuredProviders.push({ name: 'LiteLLM Proxy', value: 'litellm' });
 
   if (configuredProviders.length === 0) {
     showWarning('No API keys configured. Please add at least one API key first.');

src/types/index.ts

@@ -6,7 +6,7 @@
 // LLM CONFIGURATION
 // =============================================================================
 
-export type LLMProvider = 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai' | 'codex' | 'mock' | 'local' | 'local-agent';
+export type LLMProvider = 'openrouter' | 'venice' | 'anthropic' | 'openai' | 'xai' | 'litellm' | 'codex' | 'mock' | 'local' | 'local-agent';
 
 export interface LLMConfig {
   provider: LLMProvider;