Substack Publish

Configuration guard (run BEFORE any tool call)

This skill requires ~/.secrets/substack.env on the host. Before the first tool call of a session, verify:

test -f ~/.secrets/substack.env \
  && grep -q 'SUBSTACK_PUBLICATION_URL=' ~/.secrets/substack.env \
  && grep -q 'SUBSTACK_SESSION_TOKEN=' ~/.secrets/substack.env \
  && grep -q 'SUBSTACK_USER_ID=' ~/.secrets/substack.env && echo OK

If it prints OK, continue normally.

If not, do NOT guess and do NOT call any tool. Stop and walk the user through setup, printing exactly this: