​
Authentication

All API calls require an API key passed as a query parameter api-key.

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Request Format

We use the standard Solana sendTransaction JSON-RPC format: 
curl -X POST 'https://STELLIUM_ENDPOINT?api-key=$APIKEY' \
-d '{
    "jsonrpc": "2.0",
    "id": $UUID,
    "method": "sendTransaction",
    "params": [ 
        "<base64_encoded_tx>",
        { "encoding": "base64" }
    ] 
}'

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Parameters

ParameterTypeDescription
base64_encoded_txstringThe transaction encoded in base64 format
encodingstringMust be ‘base64’

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Response

{
    "jsonrpc": "2.0",
    "result": "transaction_signature",
    "id": "request_id"
}

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Important Notes

  1. Transactions may include a system transfer instruction to one of the Stellium tip addresses. Tipping (e.g., 0.001 SOL) improves priority, but transactions without a tip will still be routed via staked connections (subject to rate limits).
  2. Rate limits apply based on your subscription tier
  3. For optimal transaction landing, alternate between different tip addresses for consecutive transactions