diff --git a/pyproject.toml b/pyproject.toml
index e4668215..68d476e1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,7 +21,7 @@ requires-python = ">=3.12,<3.13"
 # Note that the harness includes a Claude Code CLI binary bundled inside the
 # claude-agent-sdk wheel, so the pin below also fixes the CLI version.
 dependencies = [
-    "claude-agent-sdk==0.2.110",
+    "claude-agent-sdk==0.2.128",
     "anyio==4.14.1",
     "python-dotenv==1.2.2",
     "PyYAML==6.0.3",
diff --git a/uv.lock b/uv.lock
index 0b931814..33849c4e 100644
--- a/uv.lock
+++ b/uv.lock
@@ -67,20 +67,20 @@ wheels = [
 
 [[package]]
 name = "claude-agent-sdk"
-version = "0.2.110"
+version = "0.2.128"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "anyio" },
     { name = "mcp" },
     { name = "sniffio" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/bb/98/8fdab35ed9e1a36bc7afab4d390cc5002094a4950996c079da9aa4541cc4/claude_agent_sdk-0.2.110.tar.gz", hash = "sha256:538b548bac07a22f65686abab063a902ac76ba35989d0f073c942f96248e9fa3", size = 255632, upload-time = "2026-06-24T22:11:52.342Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/a7/e8/3a9622b31f9ee22274e13a620e5e75ac38454d14538391b2fe3bc7eb76dc/claude_agent_sdk-0.2.128.tar.gz", hash = "sha256:2ac7b2b3bc56ae9037fd284c8690d3dafab9493ecd28d8974bba79a418e1b800", size = 309369, upload-time = "2026-07-25T01:48:25.884Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/aa/93/29d4fdaa13e69034faf8d3503df915b07c820e2c08e3d6a7515149cde5bb/claude_agent_sdk-0.2.110-py3-none-macosx_11_0_arm64.whl", hash = "sha256:fed0e0f4804d9f9cff80ab7d1b44142ebd1046cdd29ca74caef4c92c35fff8d8", size = 64924533, upload-time = "2026-06-24T22:11:55.612Z" },
-    { url = "https://files.pythonhosted.org/packages/aa/03/b40bb673cd93cdc3928262c1be75fde34a7bed4bf2c2c20e04218e2005ea/claude_agent_sdk-0.2.110-py3-none-macosx_11_0_x86_64.whl", hash = "sha256:62b23869d46cef6f6ff1d00ceaa5e846e2f1d297478421c835efb8fe99369d4f", size = 69704449, upload-time = "2026-06-24T22:11:59.149Z" },
-    { url = "https://files.pythonhosted.org/packages/f9/18/ab67cb5ce641333385bed55ed8e9665c00f7d30d1f6ab12f8463ddb7695f/claude_agent_sdk-0.2.110-py3-none-manylinux_2_17_aarch64.whl", hash = "sha256:324e49553c6303d6b267217dc2912652b97af2bc96503efd12095ae915b46b83", size = 74879555, upload-time = "2026-06-24T22:12:03.25Z" },
-    { url = "https://files.pythonhosted.org/packages/91/88/3627d7d14310cfec66977551263e219365244a906fc7ca1209fb0c3a6cec/claude_agent_sdk-0.2.110-py3-none-manylinux_2_17_x86_64.whl", hash = "sha256:56371dd7a2c66c0bd497dc0b3cab4193a228b196f600676393d69c0ecee37cfb", size = 75924237, upload-time = "2026-06-24T22:12:07.183Z" },
-    { url = "https://files.pythonhosted.org/packages/49/79/c9066c5c387d42c19a4b675ec1ff5219f8920cfda8ff8b527119fd69b774/claude_agent_sdk-0.2.110-py3-none-win_amd64.whl", hash = "sha256:4235d4de6d685a189c12612095ab192b759280ede1f3aed0c3e784d52c3555f9", size = 75448209, upload-time = "2026-06-24T22:12:11.283Z" },
+    { url = "https://files.pythonhosted.org/packages/45/ff/03613a38a84285cd85f114fc26d4431f545d2b3b344eb8f69f9b0f18f3c6/claude_agent_sdk-0.2.128-py3-none-macosx_11_0_arm64.whl", hash = "sha256:2e47ee95be68cb07612fd5288a40f3307763da5a5adf66d6e03ea49dc0495c9c", size = 75183825, upload-time = "2026-07-25T01:48:30.45Z" },
+    { url = "https://files.pythonhosted.org/packages/a3/df/2adbd3077f1a1cada39cd1508990d4008a8ac9ec74c801b24b1b302348b0/claude_agent_sdk-0.2.128-py3-none-macosx_11_0_x86_64.whl", hash = "sha256:55e8fa28918af5620f391692efe80527ad9f2294cec14dadeea93c5161dbefc4", size = 80305667, upload-time = "2026-07-25T01:48:35.091Z" },
+    { url = "https://files.pythonhosted.org/packages/cc/56/776a41af67a53d794b420dcd2f1075b585ed3725faa9827164f4a2e945dd/claude_agent_sdk-0.2.128-py3-none-manylinux_2_17_aarch64.whl", hash = "sha256:6c10cc1c5403b2b0b3d8deb79ad5271a8e49b9db6460193599b91f49f16b4cf7", size = 84617823, upload-time = "2026-07-25T01:48:39.297Z" },
+    { url = "https://files.pythonhosted.org/packages/17/1c/37044abbddf2141c4eeb6cc8e15a486491549a27283029d73db2c4f3c3b7/claude_agent_sdk-0.2.128-py3-none-manylinux_2_17_x86_64.whl", hash = "sha256:cc4a0f20337e227fe16f00edf7cbe109349707adb440fe51ca6c44f9f8d7d21a", size = 85663462, upload-time = "2026-07-25T01:48:43.982Z" },
+    { url = "https://files.pythonhosted.org/packages/a3/c9/ffbd8113080f87a4cd7bbfc8b00a974ea7189e3f666b5d7a2903dec7b74f/claude_agent_sdk-0.2.128-py3-none-win_amd64.whl", hash = "sha256:37b87c8e75daa2a6dc74da6d788e0981a2e5e3a6be80cfa4c287abce2bf70e0b", size = 85566882, upload-time = "2026-07-25T01:48:48.635Z" },
 ]
 
 [[package]]
@@ -300,7 +300,7 @@ dev = [
 [package.metadata]
 requires-dist = [
     { name = "anyio", specifier = "==4.14.1" },
-    { name = "claude-agent-sdk", specifier = "==0.2.110" },
+    { name = "claude-agent-sdk", specifier = "==0.2.128" },
     { name = "python-dotenv", specifier = "==1.2.2" },
     { name = "pyyaml", specifier = "==6.0.3" },
 ]