Install OpenApiErrorFormatter on the openapi blueprint's ExternalApi so
all non-2xx responses from /openapi/v1 carry the canonical ErrorBody shape
(code, message, status, optional details/hint). RFC 8628 device-flow
endpoints are unaffected — their flat {error: ...} shape is passed through
unchanged.
Also: set catch_all_404s=True when a formatter is present so unknown
routes return canonical JSON 404s (not Flask's default HTML 404).
Override _help_on_404 to suppress route suggestions, which would corrupt
the JSON contract and enumerate routes to unauthenticated callers.
Both behaviours are scoped by formatter presence — other blueprints that
construct ExternalApi without error_body_formatter are byte-identical.
Wire-level tests added to TestWireContract (3 tests, 18 total):
- 422 from @accepts validation carries code/status/details
- unknown-route 404 is canonical JSON without route suggestions
- device token POST returns RFC 8628 flat shape untouched by formatter
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
