1 files changed, 1 insertions, 0 deletions
diff --git a/API.md b/API.md
index df83415..27d4de7 100644
--- a/API.md
+++ b/API.md
@@ -169,6 +169,7 @@ List of possible error names:
 - `InvalidPasswordError`
 - `InvalidRankError`
 - `InvalidAvatarError`
+- `ProcessingError` (failed to generate thumbnail or download remote file)
 - `ValidationError` (catch all for odd validation errors)