> For the complete documentation index, see [llms.txt](https://assay.gitbook.io/assay-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://assay.gitbook.io/assay-docs/getting-started/quickstart.md).

# Quickstart

Go from a clean clone to a receipt that passes every offline check, then read a real anchor from Monad testnet.

**Where:** `@assay/receipts` (the SDK in `sdk/`), run from the `host/` package, plus one `cast call` to `ReceiptAnchor` on Monad testnet.

You build a receipt, sign it with a throwaway host key, batch it, and run `verifyReceipt` on it. No API key, wallet or MON is needed. The last step reads the first anchor Assay put on testnet.

## What you need

| Tool    | Version                            | Why                                             |
| ------- | ---------------------------------- | ----------------------------------------------- |
| Node    | 22 or newer                        | SDK, host and indexer                           |
| pnpm    | 10.20.0, through `corepack enable` | The workspace pins it                           |
| Foundry | 1.7 or newer                       | Contract tests and `cast`                       |
| Git     | any                                | Submodules for forge-std and OpenZeppelin 5.7.0 |

## Steps

1. Clone with submodules and install.

```bash
git clone --recurse-submodules https://github.com/trudransh/Assay.git
cd Assay
corepack enable
pnpm install
```

2. Run the SDK and contract tests. The Solidity tests read vectors the SDK generates, so both sides must pass.

```bash
pnpm --filter @assay/receipts test
cd contracts && forge test && cd ..
```

3. Save this file as `host/quickstart.ts`. The `host` package already depends on `@assay/receipts` and `jose`.

```typescript
import { exportJWK, generateKeyPair } from "jose";
import {
  buildBatch,
  buildReceipt,
  commitRequest,
  commitResponse,
  createHostSigner,
  newSalt,
  receiptHash,
  verifyReceipt,
} from "@assay/receipts";

// A throwaway host key. A real host loads its key from host/.keys/host.jwk.json.
const { privateKey } = await generateKeyPair("ES256", { extractable: true });
const signer = await createHostSigner(await exportJWK(privateKey), "demo-key");

const salt = newSalt();
const messages = [{ role: "user", content: "Say OK" }];
const params = { temperature: 0, max_tokens: 16 };
const output = "OK";

const body = buildReceipt({
  model: "z-ai/glm-5.3",
  host: { agentId: "erc8004:10143:1962", keyId: signer.kid, alg: "ES256" },
  req: { commit: commitRequest(salt, messages, params), params },
  res: { commit: commitResponse(salt, output), tokensIn: 9, tokensOut: 1, finish: "stop" },
});
const jws = await signer.signReceipt(body);
const hash = receiptHash(body);
const batch = buildBatch([hash]);

const result = await verifyReceipt({
  body,
  jws,
  jwks: { keys: [signer.publicJwk] },
  proof: batch.proofs.get(hash),
  root: batch.root,
  salt,
  output,
  messages,
  params,
});
console.log(result.ok, result.checks);
```

4. Run it.

```bash
pnpm --filter @assay/host exec tsx quickstart.ts
```

You should see:

```
true {
  jws: 'pass',
  hash: 'pass',
  kid: 'pass',
  merkle: 'pass',
  anchored: 'skipped',
  outputCommit: 'pass',
  promptCommit: 'pass',
  cosigned: 'skipped'
}
```

5. Read the first real anchor. Agent 1962 anchored a 2-receipt batch on 1 Oct 2026.

```bash
cast call 0x63e4F42E6d254ed6aAE735F9F4169BbFd12c1a24 \
  "anchors(uint256,bytes32)(uint32,uint64)" 1962 \
  0x5594c31b47c59350e82e11a4161b629c03ac85a36c02dc74c2630fde01086e57 \
  --rpc-url https://testnet-rpc.monad.xyz
```

The output is `2` (receipts in the batch) and `1790862482` (the anchor time in Unix seconds).

## What each result means

| Check          | `pass` means                                                 | Why it was `skipped` here                                              |
| -------------- | ------------------------------------------------------------ | ---------------------------------------------------------------------- |
| `jws`          | The signature verifies against the JWKS you passed.          |                                                                        |
| `hash`         | The body you hold is byte for byte the body the host signed. |                                                                        |
| `kid`          | The JWS `kid` equals `host.keyId` in the body.               |                                                                        |
| `merkle`       | The proof puts the receipt under `root`.                     |                                                                        |
| `anchored`     | `root` is anchored onchain under the body's agent id.        | No `onchain` client was passed, and this demo root was never anchored. |
| `outputCommit` | `salt` and `output` reproduce `res.commit`.                  |                                                                        |
| `promptCommit` | `salt`, `messages` and `params` reproduce `req.commit`.      |                                                                        |
| `cosigned`     | The key named in `req.cosigner` co-signed onchain.           | The body has no `req.cosigner`.                                        |

## Where else this shows up

| Place                                                                         | What it does with the same receipt                                   |
| ----------------------------------------------------------------------------- | -------------------------------------------------------------------- |
| [SDK reference](/assay-docs/for-developers/sdk.md)                            | Every function used above, with its inputs and errors.               |
| [Host API](/assay-docs/for-developers/host-api.md)                            | `POST /v1/chat/completions` builds this exact body for a real model. |
| [Contracts reference](/assay-docs/for-developers/contracts.md)                | `anchors` and `verifyReceipt` on `ReceiptAnchor`.                    |
| [Network and contracts](/assay-docs/getting-started/network-and-contracts.md) | The addresses used in step 5.                                        |

{% hint style="warning" %}
`skipped` is not a failure, and `result.ok` stays `true` when checks are skipped. If your app needs a check, require `result.checks.<name> === "pass"` yourself instead of reading `ok` alone.
{% endhint %}

Next: [Core concepts](/assay-docs/getting-started/core-concepts.md)


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