> ## Documentation Index
> Fetch the complete documentation index at: https://docs.uzolabs.xyz/llms.txt
> Use this file to discover all available pages before exploring further.
# SDK overview
> What @uzolabs/sdk does today, its design principles, its modules and the release plan for the rest.
`@uzolabs/sdk` gives you typed chain objects, contract addresses, [ABIs](/reference/glossary) and a BOTScan client for BOT Chain, so you can build with viem without copying values by hand.
**Early release.** This is published in `@uzolabs/sdk` 0.2.0 on [npm](https://www.npmjs.com/package/@uzolabs/sdk) and you can use it today. The API may change before 1.0, so pin the version.
## What it does
The SDK is a small TypeScript library that works alongside [viem](https://viem.sh). It doesn't replace viem. It gives viem the BOT Chain values you would otherwise look up and paste in yourself:
* **Chain objects** for mainnet (677) and testnet (968), with the RPC, explorer and Multicall3 already set.
* **Contract addresses** for WBOT, USDT, BDEX, Permit2, the Universal Router and the bridge router, typed for each network.
* **ABIs** fetched from verified contracts on BOTScan.
* **An explorer client** that reads address and contract details from BOTScan's API. It needs no API key.
* **Typed errors** with stable codes you can check in your code.
## Design principles
* **Built for viem.** Every export works with viem's own clients and actions. viem v2 is a peer dependency, so you choose its version.
* **No keys.** The SDK never touches private keys and never signs. You sign with your own wallet client.
* **No guessing.** When a value isn't public, such as a Routing API URL, the SDK asks you for it. If you don't pass it, the SDK throws `MissingConfigError` instead of falling back to a default.
* **Small imports.** Each module has its own subpath. `@uzolabs/sdk/chains` is under 2 KB gzipped.
* **Checked against the chain.** CI fails if a committed ABI no longer matches BOTScan. A nightly job checks that every address still has code.
## Modules
| Import | What it contains | Status |
| - | - | - |
| [`@uzolabs/sdk/chains`](/sdk/chains/overview) | `botChain`, `botChainTestnet` | Available in 0.2.0 |
| [`@uzolabs/sdk/contracts`](/sdk/contracts/overview) | Addresses, ABIs, constants | Available in 0.2.0 |
| [`@uzolabs/sdk/explorer`](/sdk/explorer/overview) | BOTScan client | Available in 0.2.0 |
| [`@uzolabs/sdk/bdex`](/sdk/bdex/overview) | BDEX V2 and V3 quotes, swaps, Routing API | Planned for 0.3.0 |
| [`@uzolabs/sdk/bridge`](/sdk/bridge/overview) | Bridge reads and USDT deposits | Planned for 0.4.0 |
| [`@uzolabs/sdk/paymaster`](/sdk/paymaster/overview) | EOA paymaster client | Planned for 0.5.0 |
| `@uzolabs/sdk` | Every published module, plus the [error classes](/sdk/reference/errors) | Available in 0.2.0 |
The version numbers for the planned modules come from the [SDK README](https://github.com/uzolabs/uzo-sdk#readme). No release dates have been announced. Until those modules ship, each of their pages links to a guide that does the same job with viem today.
## How it fits
```mermaid theme={"dark"}
flowchart LR
App[Your app] --> SDK["@uzolabs/sdk"]
App --> Viem[viem]
SDK -->|chain objects, addresses, ABIs| Viem
SDK -->|explorer client| BOTScan[BOTScan API]
Viem --> RPC[BOT Chain RPC]
Wallet[Your wallet] -->|signs| Viem
```
Your app creates viem clients from the SDK's chain objects and calls contracts using its addresses and ABIs. Your wallet does all the signing.
## Before you start
Read [Known limitations](/get-started/bot-chain/known-limitations). Two of them affect how you use the SDK: the mainnet RPC doesn't serve `eth_getLogs`, and there's no public WebSocket endpoint.
## Next steps
Add it to your project.
Read a block in five lines.
Addresses, ABIs and constants.
Code, issues and releases.
This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.