The Vulcx API applies rate limiting to ensure fair usage and service stability.
Limits
| Tier | Rate | Burst |
|---|
| Default | 60 requests/minute | 10 requests/second |
Rate limits are subject to change. Contact the team for higher limits if you need them for production integrations.
GET /health and GET /api/v1/tokens don’t require a key
and aren’t subject to these per-key limits.
Rate limit response
When rate limited, the API returns HTTP 429:
{
"success": false,
"error": "rate limit exceeded"
}
Retry strategy
Use exponential backoff when you receive a 429:
for i in 1 2 3; do
response=$(curl -s -w "\n%{http_code}" "https://api.vulcx.xyz/api/v1/quote?inputMint=So11111111111111111111111111111111111111112&outputMint=uSd2czE61Evaf76RNbq4KPpXnkiL3irdzgLFUMe3NoG&amount=1000000000&swapMode=ExactIn")
http_code=$(echo "$response" | tail -1)
[ "$http_code" != "429" ] && echo "$response" && break
sleep $((2 ** i))
done
async function fetchWithRetry(url: string, options?: RequestInit, maxRetries = 3) {
for (let attempt = 0; attempt <= maxRetries; attempt++) {
const response = await fetch(url, options);
if (response.status !== 429) return response;
const delay = Math.pow(2, attempt) * 1000;
await new Promise((r) => setTimeout(r, delay));
}
throw new Error("Rate limit exceeded after retries");
}
import time
import requests
def fetch_with_retry(url, max_retries=3, **kwargs):
for attempt in range(max_retries + 1):
resp = requests.request(**kwargs, url=url)
if resp.status_code != 429:
return resp
time.sleep(2 ** attempt)
raise Exception("Rate limit exceeded after retries")
Best practices
- Cache quotes. Quotes are valid for roughly 60 seconds (until
lastValidBlockHeight expires). Don’t re-fetch if you already have a recent quote.
- Batch wisely. If you need quotes for multiple pairs, space requests to stay within the rate limit.
- Use instructions endpoint. If you’re building custom transactions, one
POST /api/v1/instructions call replaces a GET /api/v1/quote + POST /api/v1/swap pair.