| name | workflow-dispatch-input-matrix |
| description | Validate every meaningful workflow_dispatch input combination before approving release-pipeline changes |
| domain | release-engineering |
| confidence | high |
| source | tank-earned |
Workflow Dispatch Input Matrix
Pattern
When a GitHub Actions workflow branches on workflow_dispatch inputs, validate the full input matrix instead of only the expected happy path.
Minimum matrix:
- Default group + blank optional inputs
- Default group + populated optional inputs
- Default group + populated invalid/stale optional inputs
- Non-default groups + blank optional inputs
- Non-default groups + populated optional inputs
- Tag-trigger path if the workflow also publishes from tags
Why it matters
Release workflows often hide bugs in guard clauses, especially when a single optional input changes the entire decision tree. A matrix check catches “works for release, breaks for validation” regressions before the failure shows up in GitHub.
Evidence to collect
- Actual run logs for the failing tuple
- Local or scripted replay of the decision tree for each tuple
- One end-to-end build/test pass after the logic change
Approval rule
Do not approve a release-workflow fix unless the reported failing tuple is shown to pass or is intentionally blocked with clearer, documented behavior.
