diff --git a/python/packages/anthropic/pyproject.toml b/python/packages/anthropic/pyproject.toml
index 57e669ec281..c3fe2742093 100644
--- a/python/packages/anthropic/pyproject.toml
+++ b/python/packages/anthropic/pyproject.toml
@@ -27,6 +27,16 @@ dependencies = [
     "anthropic>=1.11.0,<2",
 ]
 
+[dependency-groups]
+# boto3 is an ImportError-fallback optional import in _bedrock_client.py and
+# google-auth only appears in _vertex_client.py type annotations, so neither is
+# a runtime dependency. They are declared here so isolated source checks (the
+# dependency-bounds pyright probes) can resolve their APIs.
+dev = [
+    "boto3>=1.35.0,<2.0.0",
+    "google-auth>=2.0.0,<3.0.0",
+]
+
 [tool.uv]
 prerelease = "if-necessary"
 environments = [
diff --git a/python/uv.lock b/python/uv.lock
index 13726f1d35c..8d48f86d5ad 100644
--- a/python/uv.lock
+++ b/python/uv.lock
@@ -239,12 +239,24 @@ dependencies = [
     { name = "anthropic" },
 ]
 
+[package.dev-dependencies]
+dev = [
+    { name = "boto3" },
+    { name = "google-auth" },
+]
+
 [package.metadata]
 requires-dist = [
     { name = "agent-framework-core", editable = "packages/core" },
     { name = "anthropic", specifier = ">=1.11.0,<2" },
 ]
 
+[package.metadata.requires-dev]
+dev = [
+    { name = "boto3", specifier = ">=1.35.0,<2.0.0" },
+    { name = "google-auth", specifier = ">=2.0.0,<3.0.0" },
+]
+
 [[package]]
 name = "agent-framework-azure-ai-search"
 version = "1.0.0b261002"