[Carlos Savcic (serverleader)]

Problem

On macOS the first python3 on a hook's PATH is often /usr/bin/python3 (3.9). Agents run hooks without a login shell, so Homebrew/pyenv Pythons come later on PATH or only under a versioned name (python3.12). The POSIX branch of te-hook / te exec'd that first python3, te_bootstrap.py failed open on MIN_VERSION, and the plugin silently did nothing even though a usable Python was installed.

Change

POSIX branch only (Windows paths untouched):

• Probe each candidate (TE_PYTHON, python3, python3.14 … python3.10, python) and exec the first one >= 3.10.
• With none, hand off to the first Python found, so the hook still fails open via the bootstrap and te still prints "needs Python >= 3.10; set TE_PYTHON".

Cost: one extra python -c per launch on the POSIX path.

Tests

Two tests in tests/test_plugin_package.py:

• test_the_launcher_skips_a_python3_older_than_the_bootstrap_needs: fails on main, passes here.
• test_with_only_an_old_python_the_launcher_still_hands_it_the_hook: guards the fallback.

Full suite on macOS / Python 3.14: 852 passed, 16 skipped.

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[Muhammad Abdullah Butt (1AbdullahButt)]

I read both launchers at the PR head next to te_bootstrap.py (which stays importable by any Python 3 so it can answer {} itself). The probe-then-fallback order looks right for the macOS /usr/bin/python3 case. A few edge cases in the new loop (plugin/scripts/te-hook:42-50, and the same lines in plugin/scripts/te):

1. old is set even when the candidate didn't run at all. The probe exits 1 for a Python that is too old, but a pyenv/asdf shim with no version selected (pyenv: python3: command not found, exit 127) or a dangling link also lands in old=$py. If that's the only candidate, the fallback execs it, so the hook prints an error and no JSON instead of reaching the builtin {} at the end of the script. Recording only real old interpreters keeps the fail-open path:

   "$py" -c 'import sys; sys.exit(sys.version_info < (3, 10))' </dev/null >/dev/null 2>&1
   rc=$?
   [ "$rc" -eq 0 ] && exec "$py" "$dir/te_bootstrap.py" hook "$@"
   [ "$rc" -eq 1 ] && [ -z "$old" ] && old=$py

2. An explicit TE_PYTHON that is too old is now silently skipped. On main, TE_PYTHON always won. Now a later python3.12 on PATH is used instead, and the "set TE_PYTHON" message in te no longer describes what happened. If that's intended, a line in the comment would help. If not, [ "$py" = "${TE_PYTHON:-}" ] && exec ... before the probe keeps the override authoritative.

3. python3.15 is missing from the list. 3.15.0 shipped in October, so a fresh brew install python@3.15 that isn't linked as python3 would be passed over. The list will keep ageing, so adding python3.15 now (and maybe a note to extend it) is cheap.

The two new tests cover the skip and the old-only fallback. A third case with a candidate that exits 127 would pin point 1.

Reviewed with help from Claude Code.

[Aaron Li (aaron-jx-li)]

Carlos Savcic (@serverleader) Hi, please sign the CLA so we can merge your code