chore: Add path filters for integrations

.agents/skills/test-python-binding/SKILL.md

@@ -38,6 +38,13 @@ Use this skill when the change is primarily in `python/nemo_flow`,
 - The name of the mocked class should be prefixed with `mock`, not `fake`.
 - Prefer pytest fixtures over helper methods.
 - Do not repeat fixtures, if a fixture is needed in multiple test files, place it in a `conftest.py` file.
+- When creating a fixture follow this pattern:
+  ```python
+  @pytest.fixture(name="<fixture_name>"[, scope="<scope>"])
+  def <fixture_name>_fixture() -> <return_type>:
+      ...
+  ```
+  Only specify the scope argument when the value is something other than "function".
 - Prefer `pytest.mark.parametrize` over creating individual tests for
   different input types.
 

.github/ci-path-filters.yml

@@ -67,6 +67,20 @@ python_package:
   - 'rust-toolchain.toml'
   - 'uv.lock'
 
+python_integration_langchain:
+  # Includes LangGraph and DeepAgents integrations as well
+  - 'justfile'
+  - 'pyproject.toml'
+  - 'python/nemo_flow/integrations/deepagents/**'
+  - 'python/nemo_flow/integrations/langchain/**'
+  - 'python/nemo_flow/integrations/langgraph/**'
+  - 'python/tests/integrations/conftest.py'
+  - 'python/tests/integrations/deepagents_tests/**'
+  - 'python/tests/integrations/langchain_tests/**'
+  - 'python/tests/integrations/langgraph_tests/**'
+  - 'rust-toolchain.toml'
+  - 'uv.lock'
+
 wasm_package:
   - 'Cargo.lock'
   - 'Cargo.toml'

.github/workflows/ci.yaml

@@ -127,6 +127,7 @@ jobs:
     with:
       full_ci: ${{ needs.prepare.outputs.full_ci == 'true' }}
       base: ${{ needs.ci_changes.outputs.base }}
+      run_python_integration_langchain: ${{ needs.ci_changes.outputs.run_python_integration_langchain == 'true' }}
 
   ci_license_diff:
     name: License Diff
@@ -203,15 +204,16 @@ jobs:
     name: Python
     needs: [prepare, ci_changes, ci_check]
     uses: ./.github/workflows/ci_python.yml
-    if: ${{ needs.ci_check.result == 'success' && needs.ci_changes.outputs.run_python == 'true' }}
+    if: ${{ needs.ci_check.result == 'success' && ( needs.ci_changes.outputs.run_python == 'true' || needs.ci_changes.outputs.run_python_integration_langchain == 'true' ) }}
     permissions:
       contents: read
     secrets:
       CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
     with:
       ref_type: ${{ github.ref_type }}
       ref_name: ${{ github.ref_name }}
-      run_package: ${{ needs.ci_changes.outputs.run_python_package == 'true' }}
+      run_package: ${{ ( needs.ci_changes.outputs.run_python == 'true' || needs.ci_changes.outputs.run_python_integration_langchain == 'true' ) }}
+      run_integration_langchain: ${{ needs.ci_changes.outputs.run_python_integration_langchain == 'true' }}
 
   ci_wasm:
     name: WebAssembly

.github/workflows/ci_changes.yml

@@ -48,6 +48,9 @@ on:
       run_python:
         description: 'Whether Python jobs should run'
         value: ${{ jobs.changes.outputs.run_python }}
+      run_python_integration_langchain:
+        description: 'Whether LangChain, LangGraph, and DeepAgents Python integration jobs should run'
+        value: ${{ jobs.changes.outputs.run_python_integration_langchain }}
       run_python_package:
         description: 'Whether Python packaging jobs should run'
         value: ${{ jobs.changes.outputs.run_python_package }}
@@ -80,6 +83,7 @@ jobs:
       run_node_package: ${{ inputs.full_ci || steps.filter.outputs.ci == 'true' || steps.filter.outputs.node_package == 'true' }}
       run_openclaw: ${{ inputs.full_ci || steps.filter.outputs.ci == 'true' || steps.filter.outputs.shared == 'true' || steps.filter.outputs.node == 'true' || steps.filter.outputs.openclaw == 'true' }}
       run_python: ${{ inputs.full_ci || steps.filter.outputs.ci == 'true' || steps.filter.outputs.shared == 'true' || steps.filter.outputs.python == 'true' }}
+      run_python_integration_langchain: ${{ inputs.full_ci || steps.filter.outputs.ci == 'true' || steps.filter.outputs.shared == 'true' || steps.filter.outputs.python_integration_langchain == 'true' }}
       run_python_package: ${{ inputs.full_ci || steps.filter.outputs.ci == 'true' || steps.filter.outputs.python_package == 'true' }}
       run_rust: ${{ inputs.full_ci || steps.filter.outputs.ci == 'true' || steps.filter.outputs.shared == 'true' || steps.filter.outputs.rust == 'true' }}
       run_rust_package: ${{ inputs.full_ci || steps.filter.outputs.ci == 'true' || steps.filter.outputs.rust_package == 'true' }}

.github/workflows/ci_check.yml

@@ -11,6 +11,11 @@ on:
         required: false
         default: false
         type: boolean
+      run_python_integration_langchain:
+        description: 'Whether LangChain, LangGraph, and DeepAgents Python integration checks may need optional extras'
+        required: false
+        default: false
+        type: boolean
       base:
         description: 'The comparison base used for filtered pre-commit checks'
         required: false
@@ -104,12 +109,18 @@ jobs:
           FULL_CI: ${{ inputs.full_ci }}
           PRE_COMMIT_BASE: ${{ inputs.base }}
           PRE_COMMIT_HOME: ${{ runner.temp }}/.cache/pre-commit
+          PYTHON_INTEGRATION_LANGCHAIN: ${{ inputs.run_python_integration_langchain }}
           # The attribution hook syncs docs deps; do not apply repo warning policy to third-party Rust builds.
           RUSTFLAGS: ""
         run: |
           set -e
           uv tool install pre-commit==${{ steps.ci-config.outputs.pre_commit_version }}
-          uv sync --inexact --no-install-project --no-install-package nemo-flow --extra langchain --extra langgraph --extra deepagents
+          FLOW_CI_UV_SYNC_EXTRA_ARGS=()
+          if [[ "$PYTHON_INTEGRATION_LANGCHAIN" == "true" ]]; then
+            FLOW_CI_UV_SYNC_EXTRA_ARGS+=(--extra langchain --extra langgraph --extra deepagents)
+          fi
+
+          uv sync --inexact --no-install-project --no-install-package nemo-flow "${FLOW_CI_UV_SYNC_EXTRA_ARGS[@]}"
           if [[ "$FULL_CI" == "true" || -z "$PRE_COMMIT_BASE" ]]; then
             pre-commit run --all-files --show-diff-on-failure
           else

.github/workflows/ci_python.yml

@@ -19,6 +19,11 @@ on:
         required: false
         default: true
         type: boolean
+      run_integration_langchain:
+        description: 'Whether to run LangChain, LangGraph, and DeepAgents Python integration tests'
+        required: false
+        default: false
+        type: boolean
     secrets:
       CODECOV_TOKEN:
         required: false
@@ -131,6 +136,11 @@ jobs:
         working-directory: ${{ env.NEMO_FLOW_CI_WORKSPACE }}
         run: just --set ci true --set output_dir "${{ github.workspace }}" test-python
 
+      - name: Run Python LangChain integration tests
+        if: ${{ inputs.run_integration_langchain == 'true' }}
+        working-directory: ${{ env.NEMO_FLOW_CI_WORKSPACE }}
+        run: just --set ci true --set output_dir "${{ github.workspace }}" test-python-langchain
+
       - name: Upload Python coverage to Codecov
         uses: codecov/codecov-action@57e3a136b779b570ffcdbf80b3bdc90e7fab3de2 # v6
         with:

justfile

@@ -854,12 +854,12 @@ test-python:
         fi
         cargo test -p nemo-flow-python --lib
     fi
-    uv sync --inexact --no-install-project --no-install-package nemo-flow --extra langchain --extra langgraph --extra deepagents
+    uv sync --inexact --no-install-project --no-install-package nemo-flow
     activate_project_venv
     python_executable="$(project_python_executable)"
     use_project_python_source "$python_executable"
     "$python_executable" -m maturin develop --skip-install
-    "$python_executable" -m "${pytest_cmd[@]}"
+    "$python_executable" -m "${pytest_cmd[@]}" --ignore=python/tests/integrations
     if is_true "{{ ci }}" && [[ -n "$rust_coverage_out" ]]; then
         cargo llvm-cov report \
             -p nemo-flow-python \
@@ -868,6 +868,21 @@ test-python:
             --output-path "$rust_coverage_out"
     fi
 
+test-python-langchain:
+    #!/usr/bin/env bash
+    {{ bash_helpers }}
+    pytest_cmd=(pytest)
+    cd "$NEMO_FLOW_REPO_ROOT"
+    uv sync --inexact --no-install-project --no-install-package nemo-flow --extra langchain --extra langgraph --extra deepagents
+    activate_project_venv
+    python_executable="$(project_python_executable)"
+    use_project_python_source "$python_executable"
+    "$python_executable" -m maturin develop --skip-install
+    "$python_executable" -m "${pytest_cmd[@]}" \
+        python/tests/integrations/deepagents_tests \
+        python/tests/integrations/langchain_tests \
+        python/tests/integrations/langgraph_tests
+
 # --set [output_dir=<path>] [ci=true|false]
 test-go:
     #!/usr/bin/env bash
@@ -1012,7 +1027,7 @@ test-wasm:
     fi
 
 # --set [output_dir=<path>] [ci=true|false]
-test-all: test-rust test-python test-go test-node test-openclaw test-wasm
+test-all: test-rust test-python test-python-langchain test-go test-node test-openclaw test-wasm
 
 # [version] or --set ref_name=<version>
 set-version version="":

pyproject.toml

@@ -113,6 +113,10 @@ package = true
 testpaths = ["python/tests", "third_party/langgraph_tests"]
 asyncio_mode = "auto"
 
+[tool.coverage.run]
+# Exclude integration tests from coverage, since we don't run these by default
+omit = ["python/nemo_flow/integrations/*"]
+
 [tool.ty.analysis]
 # nemo_flow._native is a compiled Rust extension (built by maturin) that only
 # exists after `uv sync` / `pip install -e .`. Suppress unresolved-import for it.

python/tests/integrations/conftest.py

@@ -0,0 +1,45 @@
+# SPDX-FileCopyrightText: Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+import types
+
+import pytest
+
+
+@pytest.fixture(name="integration_langchain", scope="session")
+def integration_langchain_fixture() -> types.ModuleType:
+    """
+    Use for integration tests that require LangChain to be installed.
+    """
+    try:
+        import langchain
+
+        return langchain
+    except Exception:
+        pytest.skip(reason="langchain must be installed to run LangChain based tests")
+
+
+@pytest.fixture(name="integration_langgraph", scope="session")
+def integration_langgraph_fixture(integration_langchain: types.ModuleType) -> types.ModuleType:
+    """
+    Use for integration tests that require LangGraph to be installed.
+    """
+    try:
+        import langgraph
+
+        return langgraph
+    except Exception:
+        pytest.skip(reason="langgraph must be installed to run LangGraph based tests")
+
+
+@pytest.fixture(name="integration_deepagents", scope="session")
+def integration_deepagents_fixture(integration_langgraph: types.ModuleType) -> types.ModuleType:
+    """
+    Use for integration tests that require Deep Agents to be installed.
+    """
+    try:
+        import deepagents
+
+        return deepagents
+    except Exception:
+        pytest.skip(reason="deepagents must be installed to run Deep Agents based tests")

python/tests/integrations/deepagents_tests/conftest.py

@@ -0,0 +1,14 @@
+# SPDX-FileCopyrightText: Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+import types
+
+import pytest
+
+
+@pytest.fixture(name="integration_deepagents", scope="session", autouse=True)
+def integration_deepagents_fixture(integration_deepagents: types.ModuleType) -> types.ModuleType:
+    """
+    Override the integration_deepagents fixture to make it autouse
+    """
+    return integration_deepagents