diff --git a/CHANGELOG.md b/CHANGELOG.md
index 135230c..6dea4a9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,16 @@
 # Changelog
 
+## v3.11.9 (2026-05-26)
+
+**Antigravity Fix: Preserve functionCall/functionResponse in Gemini Sanitizer (PR #10)**
+
+### Bug Fixes
+
+- **Fix Antigravity multi-turn tool use**: The Gemini message sanitizer was incorrectly merging/dropping `functionCall` and `functionResponse` turns, causing Antigravity to think forever without responding. These turns are now always preserved as separate messages.
+- **Merge PR #10**: `fix: preserve functionCall/functionResponse in Gemini sanitizer` (qwen-chat coder)
+
+## v3.11.8 (2026-05-26)
+
 ## v3.11.8 (2026-05-26)
 
 **Vision Cache Persistence, PR #8 Merge**
diff --git a/codex-launcher_3.11.8_all.deb b/codex-launcher_3.11.8_all.deb
deleted file mode 100644
index 39826d8..0000000
Binary files a/codex-launcher_3.11.8_all.deb and /dev/null differ
diff --git a/codex-launcher_3.11.9_all.deb b/codex-launcher_3.11.9_all.deb
new file mode 100644
index 0000000..92d0edc
Binary files /dev/null and b/codex-launcher_3.11.9_all.deb differ
diff --git a/src/codex-launcher-gui b/src/codex-launcher-gui
index 6f0dc00..8ee57fc 100755
--- a/src/codex-launcher-gui
+++ b/src/codex-launcher-gui
@@ -27,6 +27,10 @@ model_catalog_json = ""
 """
 
 CHANGELOG = [
+    ("3.11.9", "2026-05-26", [
+        "Fix Antigravity: preserve functionCall/functionResponse (PR #10)",
+        "Prevents tool responses from being dropped in multi-turn sessions",
+    ]),
     ("3.11.8", "2026-05-26", [
         "Vision cache persisted across requests (PR #8 merge)",
         "No redundant vision API calls for same image URL",
diff --git a/src/codex_launcher_lib.py b/src/codex_launcher_lib.py
index 5bedfcc..309df99 100644
--- a/src/codex_launcher_lib.py
+++ b/src/codex_launcher_lib.py
@@ -83,6 +83,10 @@ model_catalog_json = ""
 """
 
 CHANGELOG = [
+    ("3.11.9", "2026-05-26", [
+        "Fix Antigravity: preserve functionCall/functionResponse in Gemini sanitizer (PR #10)",
+        "Prevents tool responses from being merged/dropped in multi-turn Antigravity sessions",
+    ]),
     ("3.11.8", "2026-05-26", [
         "Vision description cache persisted across requests (no redundant API calls for same image)",
         "Merge PR #8: fix vision cache persistence across requests",
diff --git a/src/translate-proxy.py b/src/translate-proxy.py
index 4b740b6..057c6c2 100755
--- a/src/translate-proxy.py
+++ b/src/translate-proxy.py
@@ -5562,10 +5562,16 @@ class Handler(http.server.BaseHTTPRequestHandler):
                 parts = [p for p in content.get("parts", []) if isinstance(p, dict)]
                 if not parts:
                     continue
+                # Check if this content has functionCall or functionResponse - these must be preserved
+                has_function_call = any("functionCall" in p for p in parts)
+                has_function_response = any("functionResponse" in p for p in parts)
                 text_key = "\n".join([p.get("text", "") for p in parts if "text" in p]).strip()
-                if role == "user" and text_key and text_key == last_user_text:
+                # Skip duplicate user text messages, but NEVER skip function responses
+                if role == "user" and text_key and text_key == last_user_text and not has_function_response:
                     continue
-                if role == last_role and role in ("user", "model") and sanitized:
+                # Only merge same-role messages if they don't contain function calls/responses
+                # Function calls and responses must remain as separate turns
+                if role == last_role and role in ("user", "model") and sanitized and not has_function_call and not has_function_response:
                     sanitized[-1].setdefault("parts", []).extend(parts)
                 else:
                     sanitized.append({"role": role, "parts": parts})