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

# Create a PSR schema

> Register a schema on Ethereum or Solana and manage delegates.

Schemas define the shape of attestations an issuer can publish. This guide covers creation, listing, delegation, and deprecation.

## Setup (issuer backend)

```ts theme={"dark"}
import { createWalletClient, http } from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { sepolia } from "viem/chains";
import { OpaqueClient } from "@opaquecash/opaque";

const account = privateKeyToAccount(process.env.ISSUER_PRIVATE_KEY as `0x${string}`);
const walletClient = createWalletClient({ account, chain: sepolia, transport: http(rpcUrl) });

const client = await OpaqueClient.create({
  chainId: sepolia.id,
  rpcUrl,
  walletSignature: issuerEntropySignature,
  ethereumAddress: account.address,
  ethereumWalletClient: walletClient,
  // WASM not required for PSR admin
});
```

## Create a schema

```ts theme={"dark"}
const { txHash, schemaId } = await client.createSchema("ethereum", {
  name: `kyc-passed-v1`,
  fieldDefinitions: "bool passed, string jurisdiction",
  revocable: true,
  resolver: undefined,                    // optional EVM address or Solana program
  schemaExpiry: { dateTime: "2027-01-01T00:00:00Z" },  // optional
});

console.log("schemaId:", schemaId);
await publicClient.waitForTransactionReceipt({ hash: txHash as `0x${string}` });
```

### Field definitions

Pass an ABI-style string or `FieldDef[]`:

```ts theme={"dark"}
fieldDefinitions: "bool passed, u64 score, string note"
// or
fieldDefinitions: [
  { name: "passed", type: "bool" },
  { name: "score", type: "u64" },
  { name: "note", type: "string" },
]
```

`schemaId` is derived deterministically from `(authority, name)`, so use unique names per run in tests.

## List your schemas

Returns schemas where your wallet is **authority** or **delegate**:

```ts theme={"dark"}
const schemas = await client.getMySchemas("ethereum");

for (const s of schemas) {
  console.log(s.schemaId, s.name, s.fieldDefinitions, s.deprecated);
}
```

## Add / remove delegates

Authority-only. Up to 10 delegates per schema.

```ts theme={"dark"}
await client.addSchemaDelegate("ethereum", schemaId, delegateAddress);
await client.removeSchemaDelegate("ethereum", schemaId, delegateAddress);
```

## Deprecate a schema

Irreversible; blocks new attestations:

```ts theme={"dark"}
await client.deprecateSchema("ethereum", schemaId);
```

## Solana equivalent

```ts theme={"dark"}
const client = await OpaqueClient.create({
  chainId: 11155111,
  rpcUrl: "https://ethereum-sepolia.publicnode.com",
  walletSignature,
  ethereumAddress: dummyEvmAddress,
  solana: { rpcUrl: solanaRpc, cluster: "devnet" },
  solanaWallet: { publicKey: keypair.publicKey, signTransaction },
});

const { schemaId, txHash } = await client.createSchema("solana", {
  name: `kyc-passed-v1`,
  fieldDefinitions: "bool passed, string note",
  revocable: true,
});
```

## Full E2E test reference

See `sdk/tests/psr-e2e.test.ts` (Ethereum) and `sdk/tests/psr-e2e-solana.test.ts` (Solana) for live testnet flows.