Your First Request - Ralph Studio

This guide walks you through making your first request to Ralph Studio’s RPC API. By the end you’ll have a working call that returns the current block height of the Alephium network.

Before you start

You need two things:

Your API key: find it in the Ralph Studio dashboard under Settings → API Keys
Your node slug: the unique identifier for your node, shown on the Nodes page

Both look like this:

API key: rsk_live_a1b2c3d4e5f6...
Slug: my-alephium-node

Step 1: Make the request

curl "https://rpc.ralphstudio.xyz/my-alephium-node/blockflow/chain-info?fromGroup=0&toGroup=0" \
  -H "Authorization: Bearer rsk_live_a1b2c3d4e5f6..."

Step 2: Read the response

{
  "currentHeight": 847392
}

currentHeight is the number of blocks mined on the chain from group 0 to group 0. Alephium has 16 chains (4 groups × 4 groups), so each fromGroup/toGroup pair has its own independent height.

Step 3: Handle errors

If something is wrong you’ll get a structured error:

{
  "detail": "You shall not pass"
}

HTTP status	Meaning	Fix
`401`	Missing or invalid API key	Check the `Authorization` header
`404`	Slug not found	Check your slug spelling on the Nodes page
`503`	Node is syncing	Wait a moment and retry

Step 4: Try a few more calls

Get node version

curl "https://rpc.ralphstudio.xyz/{your-slug}/infos/version" \
  -H "Authorization: Bearer YOUR_API_KEY"

Get ALPH balance for an address

curl "https://rpc.ralphstudio.xyz/{your-slug}/addresses/{address}/balance" \
  -H "Authorization: Bearer YOUR_API_KEY"

Get latest blocks

curl "https://rpc.ralphstudio.xyz/{your-slug}/blockflow/blocks?fromTs=1748390400000&toTs=1748476800000" \
  -H "Authorization: Bearer YOUR_API_KEY"

Base URL structure

Every request follows the same pattern:

https://rpc.ralphstudio.xyz/{your-slug}/{node-path}

{your-slug}: your node identifier, never changes
{node-path}: any path from the Alephium node API, passed through as-is

The indexer API uses a different prefix:

https://rpc.ralphstudio.xyz/{your-slug}/indexer/{indexer-path}

Next steps

Query an address balance

Get ALPH and token balances for any address

Submit a transaction

Build, sign, and broadcast a transfer

Read a contract

Call view functions on deployed contracts

Error handling

Retry logic and error code reference

​Before you start

​Step 1: Make the request

​Step 2: Read the response

​Step 3: Handle errors

​Step 4: Try a few more calls

​Base URL structure

​Next steps