# Inbox `cancel` Test Plan Index

## Case Files

| Case Slug | File | Coverage Note |
| --- | --- | --- |
| `cancel-marks-thread-cancelled` | [cancel-marks-thread-cancelled.md](./cancel-marks-thread-cancelled.md) | moves a non-terminal thread into `cancelled` and emits a control message |
| `cancel-persists-reason-and-artifact` | [cancel-persists-reason-and-artifact.md](./cancel-persists-reason-and-artifact.md) | persists cancel reason text and attached artifacts |
| `cancel-rejects-when-thread-missing` | [cancel-rejects-when-thread-missing.md](./cancel-rejects-when-thread-missing.md) | returns stable not-found contract when thread does not exist |