diff --git a/packages/cli/src/commands/spawn.ts b/packages/cli/src/commands/spawn.ts
index 93890fad6..db754d8d5 100644
--- a/packages/cli/src/commands/spawn.ts
+++ b/packages/cli/src/commands/spawn.ts
@@ -221,7 +221,9 @@ async function spawnSession(
     });
 
     if (composedPrompt) {
-      await new Promise((resolve) => setTimeout(resolve, 1000));
+      // Wait for agent to be fully ready (permission prompts, initialization, etc.)
+      // Longer delay ensures Claude is ready to receive input before sending prompt
+      await new Promise((resolve) => setTimeout(resolve, 2000));
       await tmuxSendKeys(sessionName, composedPrompt);
     }
 
diff --git a/packages/core/src/tmux.ts b/packages/core/src/tmux.ts
index 565d1af27..be5da26f5 100644
--- a/packages/core/src/tmux.ts
+++ b/packages/core/src/tmux.ts
@@ -129,6 +129,8 @@ export async function sendKeys(
 ): Promise<void> {
   // Clear any partial input first (matches bash reference scripts)
   await tmux("send-keys", "-t", sessionName, "Escape");
+  // Small delay to ensure Escape is processed before pasting
+  await new Promise((resolve) => setTimeout(resolve, 100));
 
   if (text.includes("\n") || text.length > 200) {
     // Use a named buffer to avoid global paste buffer race conditions
@@ -158,9 +160,11 @@ export async function sendKeys(
   }
 
   if (pressEnter) {
-    // Small delay for paste to complete before sending Enter
+    // Delay for paste to complete before sending Enter
+    // Higher delay needed when using paste-buffer to ensure tmux processes the paste
+    // before receiving the Enter keystroke (especially with Claude permission prompts)
     if (text.includes("\n") || text.length > 200) {
-      await new Promise((resolve) => setTimeout(resolve, 300));
+      await new Promise((resolve) => setTimeout(resolve, 1000));
     }
     await tmux("send-keys", "-t", sessionName, "Enter");
   }