Change the pipeline you built

scarn pipelines design --work-item-id <id>

Run the designer again, from anywhere in your repository, on a work item the current pipeline handles badly — or leave off --work-item-id and pick one (see Choosing a work item). It’s the same command you used on day one. It doesn’t start over; it edits what’s there.

What the designer reads first

Before it asks you anything, the designer reads every definition in .scarn/pipeline-builder/, summarizes each pipeline in a line, and notes where they already overlap the item you picked. If the last session’s post-push dry run failed, it raises that first and fixes it before anything else.

It only reads the local files. If a teammate pushed definitions that aren’t in your checkout, pull them first with scarn pipelines pull.

Agree on the size of the change

Before it touches a file, the designer states one verdict and waits for your yes:

Verdict	What changes
tweak	An existing pipeline: its prompts, its servers, an added step
route	A route in default.ts, or a route(...) outcome, so items like this one reach an existing pipeline
new pipeline	A new file, for a class of work item that needs a genuinely different shape

It prefers them in that order, and a pipeline that would duplicate most of an existing one’s steps counts as a tweak or a route. If you disagree, say so — it takes your verdict over its own. Details: Edit sessions.

Watch it change

The studio opens again and redraws the graph each time the designer saves a file, with the same validation issues scarn pipelines build would report. When the definitions typecheck, the designer pushes the steps (push always asks first), then builds and publishes the pipeline.

Fix a run that failed

The edit loop is the repair loop. When a step fails or the devcontainer won’t build, run scarn pipelines design again and tell the designer what happened — paste the error or point it at the run in the dashboard. See The run offer.

Edit by hand instead

The files are plain TypeScript. Edit them in your editor, run npm run typecheck (or your package manager’s equivalent) inside .scarn/pipeline-builder/, then push the steps, build, and publish each changed pipeline (details):

scarn pipelines push
scarn pipelines build
scarn pipelines publish .scarn/pipeline-builder/bug-pipeline.json

For what you can write, see Defining Steps, Building Pipelines, and Project Automations. Then commit your changes.