Notes on a request that returned 429

A request that returns HTTP 429 usually means you have reached a rate limit. Your application may have sent too many requests in a short period, used too many tokens, or reached another usage allowance. The useful response is not to send the same request again immediately. It is to understand the limit, pause when appropriate, and keep the rest of your application working.

When using Vana API, your application sends requests through a single endpoint at https://api.vanaapi.com. It supports OpenAI-compatible requests, Anthropic Messages, and Gemini native protocols. Whichever interface you use, handling rate limits belongs in the small layer of code responsible for sending requests.

§ Read the response before retrying

Start with the status code, response headers, and error message. A 429 does not always describe the same problem. A short traffic burst may clear after a pause. An exhausted quota or account restriction may require a settings or billing change instead. Use the error details to decide whether retrying makes sense.

Some responses include a Retry-After header. Its value can be a number of seconds or an HTTP date. If it is present and valid, do not retry before that time. Do not assume every provider, protocol, or response will include it.

If the requested wait is longer than your application can tolerate, stop the automatic attempt and explain the delay to the user. Quietly ignoring the header and retrying sooner only adds traffic.

§ Wait longer after each failed attempt

When there is no usable retry instruction and the error appears temporary, use exponential backoff. This means increasing the delay between attempts rather than retrying at a fixed, rapid pace.

• Begin with a short delay, such as one second.
• Double the delay after another retryable failure: two seconds, then four, then eight.
• Add a small random delay, called jitter, so multiple requests do not all restart together.
• Set a maximum number of attempts and a total time budget.

These are example settings, not Vana API rate-limit values. Choose limits that suit your application. An interactive chat might stop after a few retries, while a background task can often wait longer. If you cap your calculated backoff delay, that cap should not override a longer Retry-After instruction.

§ Check whether your SDK already retries

Before writing a retry loop, inspect your SDK’s retry settings. Some clients already retry certain errors automatically. Adding another retry layer can multiply the number of attempts and make a simple failure take much longer to return.

For example, three outer attempts combined with three SDK attempts can produce nine network requests. Prefer one clearly configured retry policy, or deliberately coordinate the layers. Also allow cancellation so a request does not keep retrying after the user leaves.

§ Reduce the pressure at the source

Retries help with temporary limits, but they do not create more capacity. If 429 responses keep appearing, reduce the traffic your application sends at once.

• Limit concurrency. Put requests in a queue and allow only a small number to run together.
• Spread out background work. Avoid launching every scheduled task at the same instant.
• Control token usage. Remove unnecessary context and set an appropriate output limit where supported.
• Reuse suitable results. Cache repeated answers when freshness and privacy requirements allow it.

§ Make the outcome visible

Show a calm message while waiting, such as “Requests are temporarily limited. Trying again shortly.” After the retry budget is exhausted, offer a manual retry rather than an endless spinner.

Log the status, attempt count, waiting time, and any available request identifier. Avoid logging API keys or sensitive prompts. If a streamed response has already started, do not silently append a restarted generation to it; treat the retry as a separate attempt.

To try this pattern, create a Vana API account and begin with one request at a time. A small, bounded retry policy is easier to understand and debug than a busy application that retries everything.