Usage limits

Technical limits below are enforced by the API. Credit balance and paid access are covered in Pricing.

Idempotency

Limit	Value
`X-Idempotency-Key` max length	64 characters
Required on	Every Open API `POST` — see Idempotency

See Idempotency.

TTS and text translation

Limit	Value
Segments / lines per request (`data` or `segments`)	50 items max
`emoWeight` (TTS)	0–1

Material upload

Topic	Detail
Upload path	Direct to CDN via presigned URLs — not through API gateway body size
Multipart	Use multipart flow for large files; part size guidance in initiate response (S3 minimum typically 5 MB per part except the last)
HTTP 413	Returned when a request body or upload exceeds allowed size

Exact upload request fields: API reference → Assets - Materials.

Rate and concurrency

Per-account rate limits and concurrency caps may apply in production. If you hit throttling, retry with backoff and contact support for higher quotas.

Error codes — including 413 Payload Too Large
Pricing — credits and 402

Text translation Error codes

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Authentication

MCP

Reliable requests

Webhooks

Assets

Products

Limits

Idempotency

TTS and text translation

Material upload

Rate and concurrency

​Idempotency

​TTS and text translation

​Material upload

​Rate and concurrency

​Related

Idempotency

TTS and text translation

Material upload

Rate and concurrency

Related