Timeout-Safe Retries for Asynchronous Video APIs

Video generation APIs often return before the media is ready. A client submits a job, receives a task identifier, checks that task until it reaches a terminal state, and then downloads the result. This changes retry behavior: a timeout on submission does not tell the client whether the server created the job.

Treat a timed-out submission as an unknown result

Suppose a client sends POST /v1/videos, but the connection closes before the response arrives. The server may have accepted the job even though the client never received its task ID. Repeating the POST immediately can create a second generation and a second charge.

Persist a client request identifier, model ID, submission time, and any returned task ID. If a timeout occurs after sending the body, mark the submission unknown and reconcile it with provider logs or a supported idempotency/status lookup before sending another POST. If the API provides neither an idempotency key nor a way to locate a job without its task ID, a client cannot safely assume that retrying is free of duplicate work.

Retry reads separately from generation

Once the task ID is known, retrying a status GET is different from retrying generation. Use bounded exponential backoff with jitter, a maximum wait time, and a clear stop condition. Stop polling when the provider reports a terminal state such as succeeded or failed; do not treat a temporary network error as a failed generation.

Keep the last observed state and timestamps. That helps distinguish a slow job from one that stopped progressing and gives support staff a useful trace without exposing the prompt or API key.

Make result handling idempotent

After success, validate that the response contains a usable result URL, then download the media to durable storage. Signed result links may expire, so store the file instead of assuming the URL will remain valid. If a download fails, retry the download for the same task rather than submitting a new generation.

Record generation and download as separate steps. A generation can succeed while a download fails; combining those states can lead an application to charge twice or lose a completed result.

Reconcile billing using provider data

Store the provider's model ID and returned usage or billing fields with the task record. Do not calculate the final charge solely from requested duration if the provider bills by model, output duration, or another measured quantity. Compare the provider response with the account usage ledger and flag discrepancies for review.

Keep credentials out of clients

Send bearer credentials only from a server-side worker. Do not put API keys in browser JavaScript, mobile application bundles, public examples, or logs. Redact authorization headers and avoid storing prompts or uploaded reference media unless the product needs them.

Example integration reference

The public 无限扩散 API documentation describes a V1 video flow with task submission, task lookup, and result download. The model square is the live source for current model availability and prices. 无限扩散 is a third-party API gateway and is not an official ByteDance service. The same retry and reconciliation pattern applies to other asynchronous generation APIs; verify each provider's task, idempotency, retention, and billing behavior before adapting it.

Operational checklist

• Can a timed-out POST be reconciled without creating another job?
• Are task IDs persisted before work is queued for polling?
• Are status retries bounded and separated from generation retries?
• Can a failed download resume from the existing task?
• Does the billing record use the provider's actual model and usage fields?
• Are credentials and sensitive prompt/media data excluded from logs?

The key rule is simple: retry the operation whose outcome is uncertain. For asynchronous video generation, that often means looking up the original task or retrying its download—not creating a new generation.