diff --git a/src/api/apiMachine.ts b/src/api/apiMachine.ts
index b8e2b570..fa4e800f 100644
--- a/src/api/apiMachine.ts
+++ b/src/api/apiMachine.ts
@@ -102,14 +102,14 @@ export class ApiMachineClient {
     }: MachineRpcHandlers) {
         // Register spawn session handler
         this.rpcHandlerManager.registerHandler('spawn-happy-session', async (params: any) => {
-            const { directory, sessionId, machineId, approvedNewDirectoryCreation, agent, token, environmentVariables } = params || {};
+            const { directory, sessionId, machineId, approvedNewDirectoryCreation, agent, token, model, environmentVariables } = params || {};
             logger.debug(`[API MACHINE] Spawning session with params: ${JSON.stringify(params)}`);
 
             if (!directory) {
                 throw new Error('Directory is required');
             }
 
-            const result = await spawnSession({ directory, sessionId, machineId, approvedNewDirectoryCreation, agent, token, environmentVariables });
+            const result = await spawnSession({ directory, sessionId, machineId, approvedNewDirectoryCreation, agent, token, model, environmentVariables });
 
             switch (result.type) {
                 case 'success':
diff --git a/src/daemon/run.ts b/src/daemon/run.ts
index 75889d14..9cf4ccc8 100644
--- a/src/daemon/run.ts
+++ b/src/daemon/run.ts
@@ -219,7 +219,7 @@ export async function startDaemon(): Promise<void> {
     const spawnSession = async (options: SpawnSessionOptions): Promise<SpawnSessionResult> => {
       logger.debugLargeJson('[DAEMON RUN] Spawning session', options);
 
-      const { directory, sessionId, machineId, approvedNewDirectoryCreation = true } = options;
+      const { directory, sessionId, machineId, approvedNewDirectoryCreation = true, model } = options;
       let directoryCreated = false;
 
       try {
@@ -325,6 +325,13 @@ export async function startDaemon(): Promise<void> {
 
         // Final merge: Profile vars first, then auth (auth takes precedence to protect authentication)
         let extraEnv = { ...profileEnv, ...authEnv };
+
+        // If model is provided via spawn options, set ANTHROPIC_MODEL (takes precedence over profile)
+        if (model) {
+          extraEnv.ANTHROPIC_MODEL = model;
+          logger.debug(`[DAEMON RUN] Model set from spawn options: ${model}`);
+        }
+
         logger.debug(`[DAEMON RUN] Final environment variable keys (before expansion) (${Object.keys(extraEnv).length}): ${Object.keys(extraEnv).join(', ')}`);
 
         // Expand ${VAR} references from daemon's process.env
@@ -388,7 +395,9 @@ export async function startDaemon(): Promise<void> {
           const cliPath = join(projectPath(), 'dist', 'index.mjs');
           // Determine agent command - support claude, codex, and gemini
           const agent = options.agent === 'gemini' ? 'gemini' : (options.agent === 'codex' ? 'codex' : 'claude');
-          const fullCommand = `node --no-warnings --no-deprecation ${cliPath} ${agent} --happy-starting-mode remote --started-by daemon`;
+          // Add --model flag if specified (for Claude agent)
+          const modelArg = model && (options.agent === 'claude' || options.agent === undefined) ? ` --model ${model}` : '';
+          const fullCommand = `node --no-warnings --no-deprecation ${cliPath} ${agent} --happy-starting-mode remote --started-by daemon${modelArg}`;
 
           // Spawn in tmux with environment variables
           // IMPORTANT: Pass complete environment (process.env + extraEnv) because:
@@ -495,6 +504,12 @@ export async function startDaemon(): Promise<void> {
             '--started-by', 'daemon'
           ];
 
+          // Add --model flag if model was specified (for Claude agent)
+          if (model && (options.agent === 'claude' || options.agent === undefined)) {
+            args.push('--model', model);
+            logger.debug(`[DAEMON RUN] Added --model ${model} to CLI args`);
+          }
+
           // TODO: In future, sessionId could be used with --resume to continue existing sessions
           // For now, we ignore it - each spawn creates a new session
           const happyProcess = spawnHappyCLI(args, {
diff --git a/src/modules/common/registerCommonHandlers.ts b/src/modules/common/registerCommonHandlers.ts
index bd4e07a5..03e5dddb 100644
--- a/src/modules/common/registerCommonHandlers.ts
+++ b/src/modules/common/registerCommonHandlers.ts
@@ -122,6 +122,8 @@ export interface SpawnSessionOptions {
     approvedNewDirectoryCreation?: boolean;
     agent?: 'claude' | 'codex' | 'gemini';
     token?: string;
+    /** Model alias (e.g., 'sonnet', 'opus') or full name. Takes precedence over environmentVariables.ANTHROPIC_MODEL */
+    model?: string;
     environmentVariables?: {
         // Anthropic Claude API configuration
         ANTHROPIC_BASE_URL?: string;        // Custom API endpoint (overrides default)