diff --git a/packages/sliceagent-core/pyproject.toml b/packages/sliceagent-core/pyproject.toml
index 409f83f..4f8048f 100644
--- a/packages/sliceagent-core/pyproject.toml
+++ b/packages/sliceagent-core/pyproject.toml
@@ -12,7 +12,7 @@ keywords = ["agent-runtime", "llm", "context-engineering", "bounded-slice", "lon
 dependencies = []
 
 [project.optional-dependencies]
-openai = ["openai==3.6.0", "httpx==0.28.1"]
+openai = ["openai==3.16.2", "httpx==0.28.1"]
 dev = ["pytest==9.1.1", "ruff==0.16.5"]
 
 [build-system]
diff --git a/pyproject.toml b/pyproject.toml
index d56d83f..4c275a8 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,7 +20,7 @@ classifiers = [
 # Pi-style supply-chain policy: every DIRECT dependency is EXACT-pinned to the uv.lock tree
 # (dependency changes are reviewed code changes, not ambient resolution). Guard: scripts/check_pinned_deps.py.
 dependencies = [
-    "openai==3.6.0",
+    "openai==3.16.2",
     "httpx==0.28.1",
     "mcp==2.1.1",   # official MCP SDK — connect external MCP servers as tools (Step 3.3)
 ]
diff --git a/uv.lock b/uv.lock
index 63dc1b5..8fd68e1 100644
--- a/uv.lock
+++ b/uv.lock
@@ -5,8 +5,8 @@ resolution-markers = [
     "python_full_version >= '3.14' and sys_platform == 'win32'",
     "python_full_version >= '3.14' and sys_platform != 'win32'",
     "python_full_version >= '3.12' and python_full_version < '3.14' and sys_platform == 'win32'",
-    "python_full_version < '3.12' and sys_platform == 'win32'",
     "python_full_version >= '3.12' and python_full_version < '3.14' and sys_platform != 'win32'",
+    "python_full_version < '3.12' and sys_platform == 'win32'",
     "python_full_version < '3.12' and sys_platform != 'win32'",
 ]
 
@@ -721,7 +721,7 @@ wheels = [
 
 [[package]]
 name = "openai"
-version = "3.6.0"
+version = "3.16.2"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "anyio" },
@@ -731,9 +731,9 @@ dependencies = [
     { name = "sniffio" },
     { name = "typing-extensions" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/ac/76/913b755a1a6b54e2d9140eb8d488aa0d47c7359b1d7eac5e864cb7913bbf/openai-3.6.0.tar.gz", hash = "sha256:18fe3f6e96390ef41ee27b152fc9effefca321c33673bd9b956a572493d3ab9b", size = 1455376, upload-time = "2026-08-28T22:29:18.268Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/e2/c6/770171ef28854d8092ee2c3df68ef97d127362b28771e6b423c948894e07/openai-3.16.2.tar.gz", hash = "sha256:e129455fc6a744276cda63a9e2f0759207bc0cf24afc4cf356bf5029e631e955", size = 1696266, upload-time = "2026-09-18T21:27:23.586Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/a1/94/805b87ecc951c49ec8f247f5e8eb324ab064bd2ad73b6a0e704dd49aa073/openai-3.6.0-py3-none-any.whl", hash = "sha256:508e2158bf971687f953b62e44b02f207792c815aac306816386d7ba34d37f5f", size = 1699841, upload-time = "2026-08-28T22:29:16.436Z" },
+    { url = "https://files.pythonhosted.org/packages/17/72/2b1fe3e303db76ab2ba0c2de2b57822869bcb588db82334d4ff3aea8acf2/openai-3.16.2-py3-none-any.whl", hash = "sha256:660a7f8307e6605342ae84ff4425412e7cd19e5e9b298f975502df2a1a9a5d5f", size = 2053568, upload-time = "2026-09-18T21:27:20.885Z" },
 ]
 
 [[package]]
@@ -1342,7 +1342,7 @@ requires-dist = [
     { name = "mcp", specifier = "==2.1.1" },
     { name = "memem", marker = "extra == 'memory'", specifier = "==2.9.7" },
     { name = "numpy", marker = "extra == 'memory'", specifier = ">=1.24" },
-    { name = "openai", specifier = "==3.6.0" },
+    { name = "openai", specifier = "==3.16.2" },
     { name = "prompt-toolkit", marker = "extra == 'tui'", specifier = "==3.0.53" },
     { name = "pytest", marker = "extra == 'dev'", specifier = "==9.1.1" },
     { name = "rich", marker = "extra == 'tui'", specifier = "==15.0.0" },
@@ -1413,7 +1413,7 @@ openai = [
 [package.metadata]
 requires-dist = [
     { name = "httpx", marker = "extra == 'openai'", specifier = "==0.28.1" },
-    { name = "openai", marker = "extra == 'openai'", specifier = "==3.6.0" },
+    { name = "openai", marker = "extra == 'openai'", specifier = "==3.16.2" },
     { name = "pytest", marker = "extra == 'dev'", specifier = "==9.1.1" },
     { name = "ruff", marker = "extra == 'dev'", specifier = "==0.16.5" },
 ]