state_call - Bittensor

Example code for the state_call JSON-RPC method. Complete guide on how to use state_call JSON-RPC in GetBlock Web3 documentation.

Executes a runtime API call — the bridge for accessing typed runtime APIs that aren't exposed as direct RPCs. This is how Polkadot.js routes calls like api.call.subnetInfoRuntimeApi.getSubnetInfo(netuid) under the hood. For Bittensor, the direct subnetInfo_* / neuronInfo_* / delegateInfo_* RPCs are often easier to use.

Substrate native JSON-RPC method. Call against a GetBlock endpoint configured for the Substrate interface. For typed SDK access, use Polkadot.js (TypeScript) or substrateinterface (Python).

Parameters

Parameter	Type	Required	Description
method	string	Yes	Runtime API method — <RuntimeApiName>_<methodName> (e.g. SubnetInfoRuntimeApi_get_subnets_info)
data	string	Yes	SCALE-encoded call data (hex)
blockHash	string	No	Block hash to execute at

Request Example

cURL

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "state_call",
    "params": [
        "SubnetInfoRuntimeApi_get_subnets_info",
        "0x"
    ],
    "id": "getblock.io"
}'

JavaScript (Axios)

import axios from 'axios';

const data = JSON.stringify({
    "jsonrpc": "2.0",
    "method": "state_call",
    "params": [
        "SubnetInfoRuntimeApi_get_subnets_info",
        "0x"
    ],
    "id": "getblock.io"
});

const config = {
    method: 'post',
    url: 'https://go.getblock.io/<ACCESS-TOKEN>/',
    headers: {
        'Content-Type': 'application/json'
    },
    data: data
};

axios(config)
    .then(response => console.log(JSON.stringify(response.data, null, 2)))
    .catch(error => console.log(error));

Python (Requests)

import requests
import json

url = "https://go.getblock.io/<ACCESS-TOKEN>/"

payload = json.dumps({
    "jsonrpc": "2.0",
    "method": "state_call",
    "params": [
        "SubnetInfoRuntimeApi_get_subnets_info",
        "0x"
    ],
    "id": "getblock.io"
})

headers = {
    'Content-Type': 'application/json'
}

response = requests.post(url, headers=headers, data=payload)
print(response.text)

Rust (Reqwest)

use reqwest::Client;
use serde_json::json;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();

    let payload = json!({
        "jsonrpc": "2.0",
        "method": "state_call",
        "params": [
                "SubnetInfoRuntimeApi_get_subnets_info",
                "0x"
        ],
        "id": "getblock.io"
});

    let response = client
        .post("https://go.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&payload)
        .send()
        .await?;

    let result: serde_json::Value = response.json().await?;
    println!("{:#?}", result);

    Ok(())
}

Response Example

{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": "0x0100000010616c70686100040100000050a02f00..."
}

Response Parameters

Field	Type	Description
result	string	Hex-encoded SCALE-encoded result of the runtime API call

Use Cases

• Calling runtime APIs that don't have direct RPC bindings

• Querying typed Bittensor runtime APIs (subnet info, neuron info) at the SCALE level

• Backwards compatibility — many things eventually move from custom RPC to runtime APIs

Error Handling

Status Code	Error Message	Cause
403	Forbidden	Missing or invalid <ACCESS-TOKEN>
-32602	Invalid params	Request parameters are missing or malformed
-32601	Method not found	Method does not exist on this interface — check whether you're calling a Substrate method on an EVM endpoint or vice versa
-32603	Internal error	Server-side error while processing the request
429	Too Many Requests	Rate limit exceeded for your plan

SDK Integration

Polkadot.js (TypeScript)

import { ApiPromise, WsProvider } from '@polkadot/api';

const provider = new WsProvider('wss://go.getblock.io/<ACCESS-TOKEN>/');
const api = await ApiPromise.create({ provider });

// Typed wrapper: api.rpc.state.call(...)
const result = await api.rpc.state.call("SubnetInfoRuntimeApi_get_subnets_info", "0x");
console.log(result.toHuman());

// Or use the raw RPC interface for any method:
// const raw = await api.rpc.send({ method: 'state_call', params: ["SubnetInfoRuntimeApi_get_subnets_info", "0x"] });

substrateinterface (Python)

from substrateinterface import SubstrateInterface

substrate = SubstrateInterface(url="wss://go.getblock.io/<ACCESS-TOKEN>/")

# Generic RPC call:
result = substrate.rpc_request("state_call", ["SubnetInfoRuntimeApi_get_subnets_info", "0x"])
print(result)