create generation with files

The multipart/form-data form of POST /v2/generate — the same endpoint as “Create Generation”, for uploading local files directly instead of passing URLs. Send each file under a field named for its type (video, image, audio), at most one of each. The application parser allows up to 5 GiB (5 × 1024³ bytes) per file, 3 files, 32 fields, 35 total parts, and 1 MiB per field. A file over the parser limit returns 413 generation_input_validation_failed, and a file over your plan limit returns 422 file_size_exceeds_plan_limit. Proxy limits may be lower; this ceiling does not guarantee a 5 GiB direct transfer. Each file is saved as an asset in your organization and passed to the generation by assetId. For large files, upload via POST /v2/assets/upload first and pass the assetId, so retries don’t resend the file. Nested fields such as input, options, segments, outputAudio, dubParams, and dialogueEdit must be sent as JSON strings in multipart requests. Image inputs are sync-3 only. If a text input requires speech synthesis and the ElevenLabs provider is temporarily unavailable, the request returns errorCode elevenlabs_service_unavailable: 504 for provider timeouts and 503 for other provider outages for unkeyed requests. Keyed uncertain outcomes return 503 IDEMPOTENCY_OUTCOME_UNKNOWN instead. An older dialogueEdit preview without segment lipsync and section expansion returns dialogue_edit_retime_required (422). Create a new preview from the same transcript and edits. A dialogueEdit that removes more speech than the surrounding footage can absorb returns errorCode dialogue_edit_removal_too_large (422). When the failing section can be identified, dialogueEditSection on the error names it; change it and create a new preview before submitting again. Retrying the same preview fails again. Send the optional Idempotency-Key header on the first request and reuse it with the same payload on retries. An accepted replay returns 200 with the original generation’s current state and Idempotency-Replayed: true. A retry after that generation ended FAILED or REJECTED starts a new generation instead (201). An API-key request without the header that is identical to one your organization sent in the last 60 seconds returns 409 DUPLICATE_SUBMISSION with the original generationId; send a unique Idempotency-Key with each generation you intend. See Idempotent Requests for key validation, conflicts, retention, duplicates, and uncertain-outcome recovery.