Configuration

import { Brickken } from 'brickken-sdk'

new Brickken({
  env: 'sandbox',            // 'sandbox' | 'production'
  baseUrl,                   // overrides env
  apiKey,
  signer,
  rpcUrl,                    // client-broadcast writes, receipt polling, and on-chain token metadata
  timeoutMs: 30_000,
  retry: { attempts: 3, baseDelayMs: 500, jitter: true },
  payment: { maxAmountBaseUnits: '50000' },
  fetch,                     // inject your own
})

Every option is optional. new Brickken() with no arguments is a valid anonymous sandbox client.

Option	Type	Default	Purpose
`env`	`'sandbox' \| 'production'`	`'sandbox'`	Selects the base URL
`baseUrl`	`string`	—	Overrides `env`. Use for any non-public deployment
`apiKey`	`string`	—	Selects API-key mode; sent as `x-api-key`
`signer`	`Signer`	—	Selects x402 mode when no key is set. See Signers
`rpcUrl`	`string`	—	JSON-RPC endpoint for `client-broadcast`, `waitForReceipt`, and token metadata
`timeoutMs`	`number`	`30000`	Per-request timeout
`retry`	`RetryPolicy`	`{ attempts: 3, baseDelayMs: 500, jitter: true }`	See Errors
`payment`	`PaymentPolicy`	`{}`	Spending controls. See Payments
`fetch`	`typeof fetch`	`globalThis.fetch`	Injectable for tests, proxies, or a runtime whose global you do not want

The constructor throws a TypeError if no fetch implementation is available — use Node 20 or newer, or pass one explicitly.

Environments

Environment	API base URL	App URL
Sandbox	`https://api.sandbox.brickken.com`	`https://dapp.sandbox.brickken.com`
Production	`https://api.brickken.com`	`https://dapp.brickken.com`

Sandbox and production are separate deployments with separate databases. An API key issued for one does not work on the other.

`env`	Base URL
`sandbox`	`https://api.sandbox.brickken.com`
`production`	`https://api.brickken.com`

An internal forge environment exists for Brickken pre-release QA — contact tech@brickken.com for its base URL and pass it as baseUrl. Read back what the client resolved:

bkn.baseUrl          // 'https://api.sandbox.brickken.com'
bkn.credentialMode   // 'api-key' | 'x402' | 'anonymous'

From the environment

Brickken.fromEnv reads the same variables the CLI and MCP server already document, including the BKN_* aliases.

const bkn = Brickken.fromEnv(process.env)

Variable	Alias	Purpose
`BRICKKEN_API_KEY`	`BKN_API_KEY`	Brickken API key
`BRICKKEN_ENV`	`BKN_ENV`	`sandbox` or `production`
`BRICKKEN_BASE_URL`	`BKN_BASE_URL`	Override the API base URL
`BRICKKEN_RPC_URL`	`BKN_RPC_URL`	JSON-RPC used for `client-broadcast`, receipts, and token metadata

An empty string is treated as unset, and an unrecognised BRICKKEN_ENV is ignored rather than guessed at. BRICKKEN_PRIVATE_KEY is deliberately not read. Turning a key into a signer is an explicit choice, never an implicit one — pass it as an override:

import { fromPrivateKey } from 'brickken-sdk/adapters/private-key'

const bkn = Brickken.fromEnv(process.env, {
  signer: fromPrivateKey(process.env.BRICKKEN_PRIVATE_KEY!),
  payment: { maxAmountBaseUnits: '50000' },
})

Overrides win over the environment, so this composes cleanly with a .env file.

Injecting `fetch`

Useful for a proxy, for request logging, or for a test that must not touch the network:

const bkn = new Brickken({
  env: 'sandbox',
  apiKey,
  fetch: async (input, init) => {
    console.log('→', input)
    return await undici.fetch(input, init)
  },
})

The injected implementation is used for API requests, for JSON-RPC broadcasting, and for receipt polling.

Namespaces

Every method the configured client exposes.

Getting Started

Core Concepts

Reference

Guides

Environments

From the environment

Injecting `fetch`

Namespaces

​Environments

​From the environment

​Injecting fetch

Namespaces

Environments

From the environment

Injecting `fetch`