import { createCoreRpcClient } from "@stacks/rpc-client";

const client = createCoreRpcClient({
  baseUrl: "http://localhost:20443",
  authToken: process.env.STACKS_RPC_AUTH_TOKEN,
});

const info = await client.request("GET", "/v2/info");
console.log(info.stacks_tip_height);

Usage with `@stacks/network`

createCoreRpcClient accepts a @stacks/network instance directly, so you can reuse an existing network configuration without duplicating the base URL or custom fetch:

import { createCoreRpcClient } from "@stacks/rpc-client";
import { STACKS_TESTNET } from "@stacks/network";

const client = createCoreRpcClient(STACKS_TESTNET);
const info = await client.request("GET", "/v2/info");

A second overrides argument lets you layer on options like authToken while still deriving everything else from the network:

const client = createCoreRpcClient(STACKS_TESTNET, {
  authToken: process.env.STACKS_RPC_AUTH_TOKEN,
});

Custom Headers

Use the headers option to attach an API key or any other custom headers to every outgoing request:

const client = createCoreRpcClient({
  baseUrl: "https://api.hiro.so",
  headers: {
    "x-api-key": process.env.STACKS_API_KEY,
  },
});

This also works alongside @stacks/network:

const client = createCoreRpcClient(STACKS_TESTNET, {
  headers: { "x-api-key": process.env.STACKS_API_KEY },
});

Example RPC Calls

Every call through client.request() is fully typed — the path autocompletes and the return type matches the OpenAPI schema.

Get node info

const info = await client.request("GET", "/v2/info");
// info is typed as NodeInfo
console.log(info.stacks_tip_height, info.burn_block_height);

Get PoX details

const pox = await client.request("GET", "/v2/pox");
// pox is typed as PoxInfo
console.log(pox.reward_cycle_length, pox.next_cycle);

Fetch account data

const account = await client.request("GET", "/v2/accounts/{address}", {
  params: { path: { address: "SP2J6ZY48GV1EZ5V2V5RB9MP66SW86PYKKNRV9EJ7" } },
});
// account is typed as AccountData
console.log(account.balance, account.nonce);

Call a read-only contract function (authenticated)

const result = await client.request(
  "POST",
  "/v2/contracts/call-read/{deployer_address}/{contract_name}/{function_name}",
  {
    params: {
      path: {
        deployer_address: "SP2J6ZY48GV1EZ5V2V5RB9MP66SW86PYKKNRV9EJ7",
        contract_name: "my-contract",
        function_name: "get-balance",
      },
    },
    body: { sender: "SP2J6ZY48GV1EZ5V2V5RB9MP66SW86PYKKNRV9EJ7", arguments: [] },
  },
);
// result is typed as ReadOnlyFunctionResult
console.log(result.okay, result.result);

Using Exported Types

All response schemas are re-exported as named types so you can annotate your own code without reaching into the generated schema:

import type { NodeInfo, PoxInfo, AccountData } from "@stacks/rpc-client";

function summarize(info: NodeInfo, pox: PoxInfo): string {
  return `tip=${info.stacks_tip_height} cycle=${pox.reward_cycle_id}`;
}

You can also derive the response type for any endpoint using CoreRpcResponse:

import type { CoreRpcResponse } from "@stacks/rpc-client";

type PoxResponse = CoreRpcResponse<"GET", "/v2/pox">;

Error Handling

Failed requests throw a CoreRpcError with structured metadata:

import { CoreRpcError, createCoreRpcClient } from "@stacks/rpc-client";

const client = createCoreRpcClient();

try {
  await client.request("POST", "/v3/block_proposal", { body: {} });
} catch (error) {
  if (error instanceof CoreRpcError) {
    console.error(error.status); // HTTP status code
    console.error(error.url);    // request URL
    console.error(error.details); // parsed error body
  }
}

Auth Behavior

authToken is attached to the authorization header only for RPC endpoints that declare rpcAuth in the spec.

Raw Client Access

When you need full control over the response (headers, streaming, middleware), use client.raw — the underlying openapi-fetch client:

const { data, error, response } = await client.raw.GET("/v2/info");
console.log(response.headers.get("x-request-id"));

Usage (CJS)

const { createCoreRpcClient } = require("@stacks/rpc-client");

const client = createCoreRpcClient({
  baseUrl: "http://localhost:20443",
});

client.request("GET", "/v2/info").then(console.log);

Generation Workflow

Types are generated by openapi-typescript from a pinned upstream URL:

https://raw.githubusercontent.com/stacks-network/stacks-core/d7f37b5388b490427d6705e17a9b016aee8fccb0/docs/rpc/openapi.yaml

Commands:

npm run generate
npm run generate:check

generate:check fails when checked-in generated output is stale.

Scripts

npm run typecheck
npm test
npm run build
npm pack --dry-run

Generator Alternatives

openapi-typescript + openapi-fetch (current choice): minimal runtime, high type safety, flexible wrapper layer.
OpenAPI Generator typescript-fetch: fuller generated SDK surface, but heavier and more verbose output.
Orval: useful when you want opinionated API client generation (often frontend-focused workflows).