Subtitle alignment failed

The API answers 422 Unprocessable Content with this problem. Its type is https://lingo.dev/docs/api/errors/vtt-alignment-failed. See Errors and status codes for the shape every error shares.

LLM returned 2 spans, expected 2 (one per source scene). Likely the model dropped or merged scenes. Cannot proceed safely — alignment must be redone manually.

Fields#

Besides the standard type, status, title and detail members, the body carries these fields. The detail text is built from them, so a client can show its own text instead.

Example#

{
  "detail": "LLM returned 2 spans, expected 2 (one per source scene). Likely the model dropped or merged scenes. Cannot proceed safely — alignment must be redone manually.",
  "reason": {
    "type": "SpanCount",
    "returned": 2,
    "expected": 2
  },
  "type": "https://lingo.dev/docs/api/errors/vtt-alignment-failed",
  "status": 422,
  "title": "Subtitle alignment failed"
}

Returned by#

• POST /v2/engines/{engineId}/glossary-terms/extract-from-vtt