diff --git a/python/packages/anthropic/pyproject.toml b/python/packages/anthropic/pyproject.toml
index 91ff2919101..db2884b00ae 100644
--- a/python/packages/anthropic/pyproject.toml
+++ b/python/packages/anthropic/pyproject.toml
@@ -85,6 +85,10 @@ exclude_dirs = ["tests"]
 executor.type = "uv"
 include = "../../shared_tasks.toml"
 
+[tool.poe.tasks.dependency-pyright]
+help = "Run Pyright over Anthropic implementation files for isolated dependency validation."
+cmd = "pyright --project pyrightconfig.dependency.json"
+
 [tool.poe.tasks.mypy]
 help = "Run MyPy for this package."
 cmd = "mypy --config-file $POE_ROOT/pyproject.toml agent_framework_anthropic"
diff --git a/python/packages/anthropic/pyrightconfig.dependency.json b/python/packages/anthropic/pyrightconfig.dependency.json
new file mode 100644
index 00000000000..6a3c479a49c
--- /dev/null
+++ b/python/packages/anthropic/pyrightconfig.dependency.json
@@ -0,0 +1,9 @@
+{
+    "extends": "../../pyproject.toml",
+    "include": [
+        "agent_framework_anthropic"
+    ],
+    "exclude": [
+        "agent_framework_anthropic/_vertex_client.py"
+    ]
+}
diff --git a/python/packages/openai/pyproject.toml b/python/packages/openai/pyproject.toml
index f1df50c9269..a8d7a9a1c96 100644
--- a/python/packages/openai/pyproject.toml
+++ b/python/packages/openai/pyproject.toml
@@ -84,6 +84,10 @@ exclude_dirs = ["tests"]
 executor.type = "uv"
 include = "../../shared_tasks.toml"
 
+[tool.poe.tasks.dependency-pyright]
+help = "Run Pyright over OpenAI implementation files for isolated dependency validation."
+cmd = "pyright --project pyrightconfig.dependency.json"
+
 [tool.poe.tasks.mypy]
 help = "Run MyPy for this package."
 cmd = "mypy --config-file $POE_ROOT/pyproject.toml agent_framework_openai"
diff --git a/python/packages/openai/pyrightconfig.dependency.json b/python/packages/openai/pyrightconfig.dependency.json
new file mode 100644
index 00000000000..6298bac03b6
--- /dev/null
+++ b/python/packages/openai/pyrightconfig.dependency.json
@@ -0,0 +1,6 @@
+{
+    "extends": "../../pyproject.toml",
+    "include": [
+        "agent_framework_openai"
+    ]
+}
diff --git a/python/scripts/dependencies/tests/test_dependency_bounds_runtime.py b/python/scripts/dependencies/tests/test_dependency_bounds_runtime.py
index 12e184057c5..3776295e82e 100644
--- a/python/scripts/dependencies/tests/test_dependency_bounds_runtime.py
+++ b/python/scripts/dependencies/tests/test_dependency_bounds_runtime.py
@@ -1,5 +1,6 @@
 # Copyright (c) Microsoft. All rights reserved.
 
+import json
 from collections.abc import Callable
 from pathlib import Path
 
@@ -196,3 +197,34 @@ def test_dependency_pyright_reuses_root_test_requirements(tmp_path: Path) -> Non
         "mcp[ws]",
     ]
     assert command[-3:-1] == ["python", "-c"]
+
+
+@pytest.mark.parametrize(
+    ("package", "module"),
+    [("anthropic", "agent_framework_anthropic"), ("openai", "agent_framework_openai")],
+)
+def test_optional_namespace_packages_define_their_own_dependency_pyright_task(package: str, module: str) -> None:
+    """Packages that type-check against deliberately optional namespaces need the probe escape hatch.
+
+    ``agent_framework_anthropic`` references ``google.auth`` and ``agent_framework_openai`` references
+    ``azure.core``/``azure.identity``, in both cases without declaring them, because those surfaces are
+    optional. A full workspace sync resolves them transitively, so repo-wide Pyright passes; an isolated
+    dependency probe does not, and the resulting ``reportMissingImports`` aborts the whole bounds gate.
+    """
+    workspace_root = Path(__file__).resolve().parents[3]
+
+    plans = _build_test_plans(workspace_root, package)
+
+    assert [plan.typing_task for plan in plans] == ["dependency-pyright"]
+
+    config = json.loads((workspace_root / f"packages/{package}/pyrightconfig.dependency.json").read_text())
+    assert config["include"] == [module]
+
+
+def test_anthropic_dependency_pyright_config_excludes_the_vertex_client() -> None:
+    workspace_root = Path(__file__).resolve().parents[3]
+    config_path = workspace_root / "packages/anthropic/pyrightconfig.dependency.json"
+
+    config = json.loads(config_path.read_text())
+
+    assert config["exclude"] == ["agent_framework_anthropic/_vertex_client.py"]