diff --git a/backend/uv.lock b/backend/uv.lock
index 16ba806..724f7d1 100644
--- a/backend/uv.lock
+++ b/backend/uv.lock
@@ -1,5 +1,5 @@
 version = 1
-revision = 2
+revision = 3
 requires-python = "==3.11.*"
 resolution-markers = [
     "sys_platform == 'win32'",
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@@ -590,7 +589,7 @@ wheels = [
 
 [[package]]
 name = "langchain-core"
-version = "1.2.19"
+version = "1.2.28"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "jsonpatch" },
@@ -602,9 +601,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "uuid-utils" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/ac/da/075720d37ebc668f48743bd540b047b2b08b8ba22b46d8f61166c5ad1d1c/langchain_core-1.2.19.tar.gz", hash = "sha256:87fa82c3eb4cc3d7a65f574cb447b5df09ec2131c8c2a0a02d4737ad02685438", size = 836647, upload-time = "2026-03-13T13:44:54.8Z" }
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 wheels = [
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+    { url = "https://files.pythonhosted.org/packages/a8/92/32f785f077c7e898da97064f113c73fbd9ad55d1e2169cf3a391b183dedb/langchain_core-1.2.28-py3-none-any.whl", hash = "sha256:80764232581eaf8057bcefa71dbf8adc1f6a28d257ebd8b95ba9b8b452e8c6ac", size = 508727, upload-time = "2026-04-08T18:19:32.823Z" },
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 [[package]]