Where are the error keys that are used in the smart service exception defined?..

On a separate note, now that Appian Forum is running on the latest release (Appian 7.1), I also wanted to highlight a change in behavior of which you might not be aware. You've authored this question on Forum as a "Post" (forum.appian.com/.../News, which means that only your followers will see this topic in their news feed. While users can also see it in their search results if the keyword they're searching for is located somewhere within your post, your question will otherwise not be readily apparent to the community.

Instead of using the "Post" functionality to ask questions on Forum, I would recommend that you use the "Ask a Technical Question" and "Ask a Business Question" actions also available from Tempo.

On a separate note, now that Appian Forum is running on the latest release (Appian 7.1), I also wanted to highlight a change in behavior of which you might not be aware. You've authored this question on Forum as a "Post" (forum.appian.com/.../News, which means that only your followers will see this topic in their news feed. While users can also see it in their search results if the keyword they're searching for is located somewhere within your post, your question will otherwise not be readily apparent to the community.

Instead of using the "Post" functionality to ask questions on Forum, I would recommend that you use the "Ask a Technical Question" and "Ask a Business Question" actions also available from Tempo.