fix(mcp): tolerate workflows without aliases

[WilliamK112]

Description

The MCP frontend now handles workflow configs that do not define workflow_alias by falling back to the workflow type. This keeps agent workflows that do define an alias unchanged while allowing FunctionBaseConfig-backed workflows such as langgraph_wrapper to be exposed as MCP tools instead of crashing during route registration.

Adds a regression test covering a workflow config object with only type=langgraph_wrapper.

Closes #1991

Testing

• PYTHONUTF8=1 UV_PROJECT_ENVIRONMENT=<repo>\packages\nvidia_nat_mcp\.venv uv run --project packages/nvidia_nat_mcp --all-groups --all-extras -- pytest -q packages/nvidia_nat_mcp/tests/server/test_mcp_front_end_plugin.py (8 passed)
• uvx ruff==0.15.0 check packages/nvidia_nat_mcp/src/nat/plugins/mcp/server/front_end_plugin_worker.py packages/nvidia_nat_mcp/tests/server/test_mcp_front_end_plugin.py
• uvx yapf==0.43.0 --diff packages/nvidia_nat_mcp/src/nat/plugins/mcp/server/front_end_plugin_worker.py packages/nvidia_nat_mcp/tests/server/test_mcp_front_end_plugin.py
• git diff --check

Note: python ci/scripts/run_tests.py --project nvidia_nat_mcp --exitfirst -- packages/nvidia_nat_mcp/tests/server/test_mcp_front_end_plugin.py synced successfully with PYTHONUTF8=1, but the helper appends the full package path after the requested file and therefore also ran unrelated package tests; it stopped at an existing OAuth TTL test failure in test_mcp_auth_provider.py. The targeted MCP frontend test above passed.

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Summary by CodeRabbit

• Bug Fixes

  • Workflows now reliably appear under their alias when one is configured, and fall back to their type name when no alias is available.
  • Improved handling of workflow registration to avoid missing entries in the available functions list.

• Tests

  • Added coverage for the fallback behavior when a workflow alias is absent.

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[coderabbitai]

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ℹ️ Recent review info

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Run ID: f2eece4f-b63a-457f-b200-f5c2ceb67645

📥 Commits

Reviewing files that changed from the base of the PR and between 201f3dc and 9f0a047.

📒 Files selected for processing (2)

• packages/nvidia_nat_mcp/src/nat/plugins/mcp/server/front_end_plugin_worker.py
• packages/nvidia_nat_mcp/tests/server/test_mcp_front_end_plugin.py

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Walkthrough

Updated _get_all_functions in the MCP front-end plugin worker to use getattr for safely retrieving workflow_alias from the workflow config, falling back to workflow_config.type when the attribute is absent, fixing a crash for configs like langgraph_wrapper that lack this attribute. Added a corresponding unit test.

Changes

Workflow Alias Fallback Fix

Layer / File(s)	Summary
Safe workflow_alias lookup with fallback test packages/nvidia_nat_mcp/src/nat/plugins/mcp/server/front_end_plugin_worker.py, packages/nvidia_nat_mcp/tests/server/test_mcp_front_end_plugin.py	_get_all_functions now uses getattr(workflow_config, "workflow_alias", None) to register workflows by alias or fall back to workflow_config.type, preventing an AttributeError for configs without workflow_alias; a new test verifies the fallback registers by type.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~5 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title is concise and clearly describes the workflow-alias fallback fix.
Linked Issues check	✅ Passed	The code and test address #1991 by falling back to workflow type when workflow_alias is missing.
Out of Scope Changes check	✅ Passed	The changes stay narrowly focused on MCP route registration fallback and a regression test.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[WilliamK112]

Label Checker is currently failing because external contributors cannot add repo labels. This PR should be labeled bug and non-breaking.

[willkill07]

/ok to test 9f0a047

[willkill07]

/merge