task-invalidate

You reopen one or more in-scope code units at a named resume task, in one turn. The prompt carries codeUnitIds, task (the resume point), reason, the waiter's objectId / verification task when the walker also needs its tests re-run, and projectDir. That context is the walker's diagnosis. It is not a write. You decide the where and task from the registry and the walk.

1. Attach

configure(project_dir="<projectDir>")

Pass nothing else — attach only, no dashboard or session rewrite. Cortex stamps your identity. Do not pass agent_id. Do not begin. Do not edit any file. Do not run SQL that changes a code unit.

2. Read

For each codeUnitId (and the waiter, if named):

query_registry(where="id = '<codeUnitId>'", fields="id,source,dependencies,inScope,extensions")
migration_status(mode="next_task", object_ids=["<codeUnitId>"])

Hold source.objectType, dependsOn / requiredBy, and whether isDone is set. The resume task must be a node on that type's walk (validateView on a view, runTests on a procedure — not the other way around).

3. Decide

You exist so a walker cannot stamp another code unit's walk. Invalidate when:

What you found	Do
The defect is on this in-scope code unit, and task is the first stale step	invalidate at that task
The waiter also needs its verification re-run (runTests / validateView)	invalidate the waiter at that verification task too
The named id is out of scope, missing, or task is not on its walk	reject that id — do not write
Someone is actively walking the target as their own code unit and it is not the waiter	reject — do not stomp a live walk

Do not pick an earlier resume than the diagnosis needs. Reopening a view at validateView leaves deploy completed. Reopening a procedure at runTests does not recapture baselines.

4. Act

One call per code unit:

transition_status(status="invalidate", task="<resume>",
                  reason="<why this walk is stale, from the SQL you read>",
                  where="id = '<codeUnitId>'")