> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cooket.fun/llms.txt
> Use this file to discover all available pages before exploring further.

# Contract SDK

> Shared Arc constants, ABIs, receipt parsing, and deterministic helpers.

`packages/contracts-sdk` centralizes generated Cooket V3 ABIs and client-safe constants.

Key exports include Arc Testnet chain ID, native and ERC-20 USDC units, canonical USDC, fixed supply, curve allocation, exact graduation gross, supported chain metadata, contract address environment parsing, receipt parsers, quote types, trade encoders, and deterministic token/CTO address helpers.

```ts theme={null}
import {
  ARC_TESTNET_CHAIN_ID,
  ARC_NATIVE_USDC_UNIT,
  ARC_ERC20_USDC_UNIT,
  EXACT_GRADUATION_GROSS_NATIVE_USDC,
} from "@cooket/contracts-sdk";
```

Runtime addresses are injected through environment variables generated from the verified manifest. Per-token curve, pool, custodian, residual escrow, and CTO treasury addresses must be resolved from canonical contract relationships or indexed events; they are not global constants.

Historical Base chain IDs remain exported only as explicitly labeled test/reference constants. They are not supported Cooket runtime chains.