add a classification to commands that they don't need a database, e.g. a third option to "online" / "offline" mode

I am having an issue running alembic history. Because I have migrations which rely on modules within my project, I get a ModuleNotFoundError when running alembic history. I can work around this by setting the python path but I would rather the command was working "out of the box".

I tried setting revision_environment to true in the ini file, along with correcting the path in env.py. This results in an error caused by attempting to connect to the database, since the details required to connect are not available.

Is there an existing approach to being able to run alembic history with the revision environment but without the connection? If not would it make sense to alter the behaviour of history to load the environment in offline mode except where required (e..g when executed with --indicate_current)

Start with the alembic history command and the env.py and ini configuration described in the issue; compare normal and offline execution, including --indicate_current. Determine how revision environments should load without a database connection, then verify that history works with project modules while connection-dependent behavior remains available.