Core concepts

Script versions

A script is not one body of code but a line of versions. A version is a snapshot of the code together with the input and output schemas it was written against, and every run targets one.

That pairing is the point: an argument that worked last week works today, because the schema that accepted it is part of the same snapshot as the code that read it.

Draft, then promoted

A version is editable while it is a draft, and never again once it is promoted.

create_draft_script_version takes the script as it stands and opens a draft from it.
patch_draft_script_version edits that draft in place — no new version each time you fix a selector.
Run it by its version_id to test it. Nothing that calls the script by name is affected yet.
promote_script_version makes it the current version. From then on, that is what callers get.

A draft you abandon is discarded with delete_draft_script_version. list_script_versions shows the line, newest first, with which one is current and which are still drafts.

Running an old version

Both the MCP and the CLI take a version id in place of “whatever is current”:

npx @reduck-ai/cli@latest run --script linkedin.com/get_post url=… --version-id <id>
npx @reduck-ai/cli@latest read linkedin.com/get_post --version-id <id> --code

Useful for checking whether a site changed or a script did.