diff --git a/scripts/claw.js b/scripts/claw.js
index 04a4228c..121859a1 100644
--- a/scripts/claw.js
+++ b/scripts/claw.js
@@ -89,13 +89,17 @@ function askClaude(systemPrompt, history, userMessage, model) {
   if (model) {
     args.push('--model', model);
   }
-  args.push('-p', fullPrompt);
+  args.push('-p');
 
-  // On Windows, the `claude` binary installed via npm is `claude.cmd`.
-  // Node's spawn() cannot resolve `.cmd` wrappers via PATH without shell: true,
-  // so this call fails with `spawn claude ENOENT` on Windows otherwise.
+  // On Windows the `claude` binary installed via npm is `claude.cmd`/`claude.ps1`,
+  // and Node's spawn() cannot resolve those wrappers via PATH without shell: true.
+  // But shell mode concatenates args *unescaped*, so a multi-line prompt passed as
+  // an arg gets mangled (newlines and the `===` section markers truncate it, and
+  // claude receives an empty prompt). Fix: send the prompt over stdin via `input`
+  // and keep only the short, safe flags (`--model`, `-p`) as args.
   // 'claude' is a hardcoded literal here (not user input), so shell mode is safe.
   const result = spawnSync('claude', args, {
+    input: fullPrompt,
     encoding: 'utf8',
     stdio: ['pipe', 'pipe', 'pipe'],
     env: { ...process.env, CLAUDECODE: '' },