# Which issue(s) this PR fixes
- Fix issue that was causing our openapi schema to return HTTP 500 + add
an integration test which fetches the `.yaml` schema and validates that
the endpoint returns HTTP 200 (should hopefully prevent this from
happening again).
- add a few more type hints along the way
## Checklist
- [x] Unit, integration, and e2e (if applicable) tests updated
- [x] Documentation added (or `pr:no public docs` PR label added if not
required)
- [x] `CHANGELOG.md` updated (or `pr:no changelog` PR label added if not
required)