For AI agents: the complete documentation index is available at https://mfeflow.github.io/mfeflow/llms.txt, the full documentation bundle is available at https://mfeflow.github.io/mfeflow/llms-full.txt, and this page is available as Markdown at https://mfeflow.github.io/mfeflow/errors/E212.md.
mfeflow

    MFEFLOW_E212

    Applying the plan failed.

    Fix

    Everything already written was rolled back. Fix the cause above and run the command again.