[salignatmoandal]

The PAI-Bench-C launcher exits before setup from its current .agents/skills/evaluation/ location because it only recognizes the legacy cookbooks/cosmos3 root. Even after recognizing Framework, its checkout selection would otherwise fall back to a nested clone under packages/.

Recognize the containing Framework checkout by pyproject.toml and cosmos_framework/, and reuse it before considering legacy nested checkouts. Preserve explicit COSMOS3_REPO overrides, clone destinations, and legacy cookbook layouts. Document checkout selection and the command for the new CPU path tests.

Validation:

• Before the fix, three path tests failed on the Framework layout; the legacy and invalid-root cases passed.
• All seven CPU tests now pass: current layout, spaces and unrelated working directory, containing-checkout precedence, explicit checkout and clone overrides, legacy checkouts and clone fallback, and invalid-root rejection before setup.
• python3 -m unittest discover -s .agents/skills/evaluation/cosmos3/generator/paibench_c -p test_launcher_paths.py -v
• bash -n .agents/skills/evaluation/cosmos3/generator/paibench_c/run_paibench_c.sh
• Ruff lint and format checks on the new test, and git diff --check, passed.

The tests exercise the actual bootstrap section before setup side effects; the invalid-root case executes the complete script. No model downloads, GPU inference, or benchmark scoring were performed. Shard counting and evaluation coverage remain outside this change.